chemistry

QUESTION BANK

CHEMISTRY-XII

THE SOLID STATE

CHAPTER - 1 (Weightage 4 marks)

VERY SHORT ANSWER TYPE QUESTIONS (OF 1 MARK EACH)

1. What is the number of atoms per unit cell in a body centered cubic structure?

2. Name an element with which silicon can be doped to give a p-type semiconductor.

3. A cubic solid is made of two elements X and Y. Atoms Y are at the corners of the cube and X at the body centre. What is the formula of the compound?

4. Why is common salt sometimes yellow instead of being pure white?

5. Why are Frenkel defects not found in pure alkali halides?

6. What makes alkali metal halides sometimes colored which are otherwise colorless?

7. What is the effect of Schottky and Frenkel defects on the density of crystalline solids?

8. What is Curie temperature?

9. Why is Frenkel defect found in AgCl?

10. Why are solids rigid ?

11. Name the non stoichiometric point defect responsible for colour in alkali halides.

12. Define the term space lattice?

13. Why is glass considered a super cooled liquid ?

14. What is the coordination number of an octahedral void?

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15. What type of solids are electrical conductors, malleable and ductile?

SHORT ANSWER TYPE QUESTIONS : ( OF 2 MARKS EACH)

16. How can you determine the atomic mass of an unknown metal if you know its density and the dimension of its unit cell? Explain your answer.

17. How does amorphous silica differ from quartz?

18. Define the term amorphous .Give a few examples of amorphous solids.

19. What is a semiconductor? Describe two main types of semiconductors, giving examples.

20. Explain how vacancies are introduced in an ionic solid when a cation of higher valency is added as an impurity in it

21. What type of substances would make better permanent magnets, ferromagnetic or ferromagnetic? Justify your answer.

22. Assign reason why some of the very old glass objects appear slightly milky instead of being transparent.

23. An element crystallizes in a structure having fcc unit cell with edge length of 200 pm. Calculate its density, if 200 g of this element contains 24 x 1023 atoms.

24. The length of the unit cell edge of a body centered metal crystal is 352 pm. Calculate the radius of an atom of a metal.

25. An element (z=60) having face centered cubic unit cell has a density of 6.23 g/cm3.What is edge length of unit cell.

26. State the difference between schottky and frenkel defects. Which of the two changes the density of the solids.

27. An element crystallizes in the simple cubic structure .Its density is 8 g/em3 and its 200 g contains 24x10 23 atoms .Calculate the edge length.

28. How do electrical resistivity of the following class of materials vary with temperature?

Semiconductor, metallic conductor, insulator.

29. What is the coordination number of an octahedral void? Which of the following lattices has the highest packing efficiency

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(i) FCC

(ii) BCC

(iii) simple cubic

30. Atoms of element B form hcp lattice and those of the element A occupy 2/3rd of tetrahedral voids .What is the formula of the compound formed by these elements A and B?

SHORT QUESTIONS (3 MARKS ONLY)

31. A compound is formed by two elements M and N. The element N forms ccp and atoms of M occupy 1/3rd of tetrahedral voids.What is the formula of the compound?

32. A solid A is very hard electrical insulator in solid as well as in molten state and melts at extremely high temperature.What type of solids is it.

33. In terms of band theory what is the difference

(i) Between a conductor and an insulator

(ii) Between a conductor and a semiconductor?

34. Distinguish between Hexagonal and monoclinic unit cell.

35. What makes a glass different from a solid such as quartz/Under what conditions could quartz be converted into glass?

36. What is a semiconductors ?Describe two main types of semiconductors , giving examples .

37. What makes a glass different from solid such as quartz ?

38. How does amorphous silica differ from quartz?

39. How do electrical resistivity of the following class of materials vary with temperature?

40. What type of stoichiometric defect is shown by: Zns and AgBr?

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QUESTION BANK ‐XII

SOLUTIONS

CHAPTER ‐ 2 (Weightage 5 marks)

VERY SHORT ANSWER TYPE QUESTIONS: ( OF ONE MARK EACH)

1. What do you mean by Colligative Properties?

2. Define osmotic pressure.

3. Why is an increase in temperature observed on mixing Chloroform with Acetone?

4. State Raoults law for a binary solution containing volatile components.

5. Why is osmotic pressure considered as a colligative property.

6. Out of 1M solution of sugar and 1M solution of urea which will have greater boiling point ?

7. Why do doctors advise gargles by saline water in case of sore throat?

8. Give an example of nearly ideal solution?

9. What are maximum boiling azetropes? Give one example.

10. Why is the cooking temperature in pressure cooker higher than in open pan?

11. A and B liquids on mixing produced a warm solution .Which type of deviation is there and why?

12. Give reason when 30 ml of ethyl alcohol and 30ml of water are mixed the volume of resulting solution is more than 60ml.

13. When is the value of Vant Hoff factor more than one?

14. Give an example of a compound in which hydrogen bonding results in the formation of a dimer.

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15. What are isotonic solutions?

SHORT ANSWER TYPE QUESTIONS: ( OF 2 MARKS EACH)

16. Name two factors on which the vapour pressure of the liquid depends.

17. What type of non idealities are exhibited by cyclohexane –ethanol and acetone chloroform mixture? Give reasons for your answer.

18. The solution of a non volatile solute boils at higher temperature than the pure solvent .Show this relationship on a graphic diagram.

19. For determining molar masses of macromolecular substances in solutions the osmotic pressure measurement method is preferred over measurement method of any other colligative property of solution. Give two reasons for it.

20. Explain with a suitable diagram and appropriate examples why some non ideal solutions show positive deviation from ideal behaviour.

21. How is relative lowering of vapour pressure defined for a solution consisting of volatile solvent and non volatile solute? How is this function related to the mole fraction of the solvent and of the solute?

22. Amongst the following compounds, identify which are insoluble, partially soluble and highly soluble in water?

(i) Phenol (ii) NaClO4 and Water (iii) methanol and acetone

(iv) I2 and CCl4 (v) acetonitrile (CH3CN) and acetone (C3H6O)

24. 0.6ml of acetic acid (CH3COOH), having density 1.06 g ml‐1, is dissolved in 1 litre of water. The depression in freezing point observed for this strength of acid was 0.02050C. Calculate the van’t Hoff factor and the disassociation constants of acid.

25. Vapour pressure of pure water at 298K is 23.8 mm Hg. 50 g of urea (NH2CONH) is dissolved in 850g of water. Calculate the vapour pressure of water for this solution and its relative lowering.

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26. 100g of liquid A (molar mass 140 g mol‐1) was dissolved in 1000g of liquid B (molar mass 180 g mol ‐1) . The vapour pressure of pure liquid B was found to be 500 torr. Calculate the vapour pressure of pure liquid A and its vapour pressure in the solution if the total vapour pressure of the solution is 475 torr.

27. Determine the osmotic pressure of a solution prepared by dissolving 25 mg of K2SO4 in 2 litres of water at 25

0C, assuming that it is completely dissociated.

28. What role does the molecular interaction play in solution of alcohol and water?

29. Why do gases always tend to be less soluble in liquids as the temperature is raised?

30. With the help of suitable diagrams explain positive and negative deviations from Raoults law?


31. ‐State Henrys law and mention some of its important application?

32. Why is Ether not miscible in Water?

33. What are Hypertonic and Hypotonic Solutions?

34. What factors are responsible for deviations from Raoults law?

35. How is osmotic pressure dependent upon number of moles of solute?

36. How is molality of solution differs from its molarity?

37. Two liquids X and Y boils at 1100Cand 1300C respectively, which of them has higher vapour pressure at 500C

38. Why is the cooking temperature in pressure cooker is higher than in an open pan?

39. State the condition resulting in reverse osmosis?

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40. What is antifreeze and also give an example?

LONG ANSWER TYPE QUESTION: (OF 5 MARKS EACH)

41. Explain giving examples the term colligative molality.Why do we

sometimes get abnormal molecular masses of the substances using colligative properties of the solution?

42. Phenol associates in benzene to certain extent to form dimer .A solution contains 20 x10‐3 kg of phenol in 1kg of benzene has its freezing point decreased by 0.61 K.Calculate the fraction of phenol that has dimerised. (Kf for benzene= 5.512)

43. The osmotic pressure of blood is 8.21 atm at 37oC. How much glucose should be added per litre for an intravenous injection that is at same osmotic pressure as blood?

44. Explain giving examples the term Colligative Molality? Why do sometime we get abnormal molecular masses of substance using colligative property?

45. Vapour pressure of pure Acetone and Chloroform at 328K are 741.8 mm Hg and 632.8 mm Hg respectively. Assuming that they form ideal solution over the entire range of composition whether it is positive or negative deviation from the ideal solution?

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ELECTROCHEMISTRY

CHAPTER‐3

WEIGHATGE—5

VERY SHORT ANSWER TYPE QUESTIONS (OF 1 MARK EACH)

1. Can you store copper sulphate solutions in a zinc pot ?

2. Why does the conductivity of a solution decrease with dilution?

3. What are primary cells ?

4. What is over voltage ?

5. What are secondary cells

6. Define corrosion.

7. State Faradays first law of electrolysis .

8. State Faradays second law of electrolysis.

9. HCl does not give an acidic solution in benzene.Why?

10. Under what condition will a galvanic cell send no current into outer circuit ?

11. How does cathodic protection of iron operate?

12. How fluoride can be converted to fluorine?

13. Suggest two materials other than hydrogen that can be used as fuels in fuel cells.

14. Rusting of iron is quicker in saline water than in ordinary water. Why is it so?

15. Express mathematically relationship among the resistance specific conductivity and cell constant

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SHORT ANSWER TYPE QUESTION : (2MARKS EACH)

16. .How much copper is deposited on the cathode of an electrolytic cell if a current of 5 ampere is passed through a solution of copper sulphate for 45 minutes?

17. Why is that Aluminum cannot be obtained by electrolysis of an aqueous solution of Aluminum?

18. What do you mean by Faraday’s Constant?

19. Derive relationship between Resistance, Specific Conductivity and Cell Constant?

20. HCl does not give an acidic solution in Benzene and why?

21. State two advantages of H2‐O2 fuel cell over ordinary cells.

22. What is meant by specific conductivity of a solution / The specific conductance of a 0.12 N solution of an electrolyte is 2.4 x10‐2S/cm .Calculate its equivalent conductance.

23. Write the cell reactions which occur in lead storage battery

(i) When the battery is in use and

(ii) When the battery is on charging.

24. A solution of Ni(NO3) is electrolysed between platinum electrodes using a current of 5 amperes for 20 minutes .What mass of Ni is deposited at the cathode?

25. Calculate the potential of hydrogen electrode in contact with a solution whose pH is 10.

26. Explained how rusting of iron is envisaged as setting up of an electrochemical cell.

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27. A solution of CuSO4 is electrolysed for 10 minutes with a current of 1.5 amperes .What is the mass of copper deposited at the cathode?

28. Write the chemistry of recharging the lead storage battery, highlighting all the materials that are involved during recharging.

29. Define conductivity and molar conductivity for the solution of an electrolyte .Discuss their variation with concentration.

30. State Faraday’s second law of electrolysis?

SHORT ANSWER TYPE QUESTION : (3MARKS EACH)

31. How much Cu is deposited on the cathode of an electrolysis cell if a current of 5A is passed through a solution of Copper Sulphate?

32. Explain Kohlrausch Law of independent migration of ions and also mention one application of it?

33. What is meant by specific conductivity of a solution and how it is related with cell constant?

34. What is meant by molar conductivity of a solution? The specific conductivity of 0.4M solution of KCl at 298 K is 4.96S/cm calculate its molar conductivity?

35. What are fuel cells?

36. Write the electrode reaction of fuel cell which uses the reaction of Hydrogen with Oxygen?

37. Explain mercury cell with reactions at anode and cathode?

38. Why the potential of the mercury cell remains constant throughout the life?

39. What is corrosion

40. How does molar conductivity varies with concentration for weak electrolyte?

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LONG ANSWER TYPE QUESTIONS (5 MARKS EACH)

41. Explain the term electrolysis .Write the reactions at cathode and anode when following substances are electrolysed :‐

(i) Molten NaCl

(ii) Aqueous solution of NaCl

42. What is meant by electrochemical series? How does it help in :‐

(i) comparing the relative oxidizing or reducing powers of different elements

(ii) predicting whether metal will react with the acid to give hydrogen gas or not ? How the electrode potential can be used to predict the products of electrolysis of an an aqueous solution of an electrolyte? Explain with a suitable example?

43. (a) Explain the following : ‐

(i) Electrolysis of aqueous solution of NaCl gives H2 at cathode and Cl2 gas at anode.

(ii) Electrolysis of aqueous solution of CuBr2 gives Cu at cathode and Br2 at the anode.

(ii) A Bromide or iodide on electrolysis give Br2 or I2 at the anode whereas of fluoride does not give at the anode.

(b) Describe standard hydrogen electrode and give one of its applications.

44 (i) Why does a dry cell become dead after a long time even if it has not been used?

(ii) Why does a mercury cell gives a constant voltage throughout its life?

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45 Blue colour of Copper Sulphate solution is slowly discharged when an iron rod is dipped into it. Explain this by calculating Gibbs free energy with the help of Electrochemical series?

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CHEMICAL KINETICS

CHAPTER‐4

WEIGHTAGE—5

VERY SHORT ANSWER TYPE QUESTIONS:(1 MARK EACH)

1. What is difference between average rate and instantaneous rate of a chemical reaction?

2. What is the order of reaction if the rate of reaction is independent of concentration of all the reactants?

3. Define rate of reaction.

4. What are the units of rate constant for a first order reaction?

5. Name one zero order reaction.

6. What ate the units of rate constant for a first order reaction?

7. What is the order of radioactive decay?

8. Give the units for specific reaction rate constant for a zero order reaction.

9. What is meant by elementary step of a reaction?

10. How does the value of rate constant vary with reactant concentration?

11. The reaction A+B‐‐C has a zero order .What is the rate equation?

12. What are the units of rate constant for a second order reaction?

13. Why is it that instantaneous rate of reaction does not change when a part of the reacting solution is taken out?

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14. Is there any reaction for which reaction rate does not decrease with time?

15. When is the rate of reaction equal to specific reaction rate?

SHORT ANSWER TYPE QUESTIONS ( OF 2 MARKS EACH )

16. What is known as activation energy ? How is the activation energy affected by :‐ (i) The use of a catalyst and (ii) 11A rise in temperature?

17. What aspect of a reaction is influenced by presence of catalyst which increases the rate or possibility of the reaction?

18. State the role of activated complex in the reaction and state its relation with activation energy.

19. The rate constant for a first order reaction becomes six times when the temperature is raised from 350K to 400K. Calculate the activation energy for the reaction.

20. The conversion of molecules X to Y follows second order kinetics. If concentnration of X is increased to three times how will it affect the rate of formation of Y.

21. What will be the effect of temperature on rate constant?

22. Draw a schematic graph showing how the rate of reaction changes with change in concentration of reactant.

23. Show graphically how the rate of reaction depends on the concentration of reactant when depends on the concentration of reactant when there is only reactant and the reaction is first order?

24. Show that in a first order reaction ,time required for completion of 99.9% is 10 times of half life of the reaction.

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25. The rate of the chemical reaction doubles for an increase of 10K in absolute temperature from 298 K. Calculate activation energy?

26. State rate law for chemical reaction

27. Why is that instantaneous rate of reaction does not change when a part of reacting solution is taken out?

28. When is the rate of reaction is equal to specific reaction rate.

29. Derive equation for the first order reaction?

30. The rate of reaction X gives Y becomes 8 times when the concentration of the reactant X is doubled. Write the rate law for the reaction?

SHORT ANSWER TYPE QUESTIONS ( OF 3 MARKS EACH)

31. What is the difference between average rate and instantaneous rate of a chemical reaction?

32. The half life of reaction is 50 mins. What will be the order of the reaction if reaction goes to completion in 100 mins?

33. Define molecularity ?

34. Derive half life of a reaction ?

35. What is the useful of initial rate method ?

36. What is known as activation energy ?

37. What are photochemical reactions?

38. What will be the effect of temperature on the rate constant?

39. State the role of activated complex in the reaction and state its relation with activation energy.

40. What aspect of a reaction is influenced by presence of catalyst which increases the rate or possibility of the reaction?

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LONG ANSWER TYPE QUESTIONS (OF 5 MARKS EACH)

41. (a) The rate of the first order reaction is 0.004 mo/l/s at 10 min and 0.03 at 20 min after initiation .Find half life of the reaction.

(b) The rate constant for an reaction A ‐‐‐‐‐‐ B is 4.5 x10‐3 min‐1.If the initial conc. Of A is 1M ,calculate the rate of reaction after 1hr.

42. The half life for radioactive decay of d14 C is 5730 years . An archaeological artifact contain wood has only 80% of the 14 C. Found in a living tree Estimate the age of sample?

43. Time required to decomposed SO2Cl2 to half of its initial amount is 60 minutes . If the decomposition is a first order reaction, calculate the rate constant of the reaction.

44. The rate constants of a reaction at 500K and 700 K are 0.02 per second and 0.07 per second respectively .Callculate the values of activation energy and arhenius factor.

45. Calculate the value of activation energy , if rate of reaction doubles when rise in temperature from 295 K to 305K takes place.

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SURFACE CHEMISTRY

CHAPTER 5

(WEIGHTAGE‐3 MARKS)

VERY SHORT ANSWER QUESTIONS (1 MARK EACH)

1. In what way is a sol different from a gel.

2. What is meant by the term peptization?

3. Why do colloidal solution exhibits Tyndall effect ?Mention one application of emulsion?

4. What is electrophoresis due to?

5. How does soap help in washing clothes?

6. How does chemical adsorption of a gas on a solid vary with temperature?

7. Name two industrial process in which heterogeneous catalyst are employed.

8. Of NH3 and N2 which gas will be adsorbed more readily on the surface of charcoal and why?

9. How does the addition of alum purify water?

10. What is electrophoresis?

11. How is dialysis carried out?

12. Give an example of hetrogenous catalysed reaction?

13. In what way is a sol different from gel?

14. Give an example of associated colloid?

15. What is tyndol effect?


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16.What is meant by critical micelle concentration?

17. What happens when freshly prepared ferric hydroxide is shaken with a little amount of dilute ferric chloride?

18. Why is adsorption is always exothermic ?

19. Why are powdered substances more effective adsorbent than their crystalline forms?

20. Why is necessary to remove CO when ammonia is obtained by Habers process?

21. What is sorption?

22. What is observed when sodium chloride is added to a colloidal solution of ferric hydroxide ?

23. What is the function of emulsifying agent?

24. Action of soap is due to emulsification and micelle formation comment.

25. Why is the ester hydrolysis slow in the beginning and becomes faster after sometimes?

26. Explain what is observed :‐

(i) When a beam of light is passed through a colloidal sol.

(ii) An electrolyte NaCl is added to hydrated ferric oxide sol.

(iii) Electric current is passed through a colloidal sol.

27 Explain the term with suitable example :‐

(i) Alcosol

(ii) Aerosol

(iii) Hydrosol

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28. How are colloids classified on the basis of physical states of the dispersed phase and dispersion medium?

29. What is the difference between multimolecular and macromolecular colloids ? Give one example of each .How are associated colloids different from these two types of colloids?

30. Discuss the effect of pressure and temperature on the adsorption of gases on solids?


31. What is the sign of enthalpy and entropy when bromine gas get adsorbed on charcoal?

32. Why sky appears blue?

33. How can a colloidal solution and true solution of the same colour be distinguished from each other ?

34. Why is smoke passed through charged plates before allowing it to come out of chimneys in factories?

35. What are aerosols ?Give two examples.

36. What is meant by CMC?

37. What role does adsorption play in hetrogenous catalysis?

38. What happens when electric field is applied to a colloidal solution?

39. Why do colloidal solution exhibit tyndol effect?

40. What is sorption?

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GENERAL PRINCIPLES AND PROCESSES OF ISOLATION OF ELEMENTS

CHAPTER 6

(WEIGHTAGE‐3)

VERY SHORT ANSWER TYPE: (1 MARK EACH)

1. Name the 3 most abundant element in the earth crust.

2. Give composition of Dolomite .

3. Name sulphides ores of (i) Fe (ii) Mn

4. Name the element present in sea weeds .

5. Give formula of (i) Haematite (ii) Magnetite.

6. What do mean by roasting and calcinations.?

7. Write short notes on Zone refininf and Liquation ?.

8. What is Van arkel method of refining metal? Explain by giving an example.

9. Which is better reducing agent at 7100 C ,C or CO?

10. Name the reducing agent used in aluminiothermic process.

11. Name the element present in Sea Weed?

12. What is meant by chromatography?

13. Name halide ore of Ag and K?

14. Name one oxide ore of Sn and Fe?

15. State the role of Silica in metallurgy of Copper?

SHORT ANSWER TYPE QUESTION : ( OF 2 MARKS EACH)

16. Why copper matte is put in Silica lined of Aluminum?

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17. What is the principle of separation of metal ions in qualitive analysis ?

18. Write short notes on Vapour phase refining and electrolytic refining?

19. Copper and silver are below hydrogen electrochemical series and yet they are found in the combined state as sulphide in nature comment.

20. What metals are generally extracted by the electrolytic process? What positions do these metals generally occupy in the periodic table?

21. Write the name of the places in India where the following ores are found and give their formulae: Haematite and Bauxite.

22. Indicate the temperature at which carbon can be used as reducing agent for FeO.

23. Name the metals which are associated with the following terms :‐

(a) Bessemers converter

(b) Blast furnance

24. Is it true under certain conditions Mg can reduce SiO2 and Si can reduce MgO? What are those conditions?

25. What is the thermodynamic consideration in the choice of a reducing agent in metallurgy?

26. Although thermodynamically feasible in practice magnesium metal is not used for the reduction of alumina in the metallurgy of aluminium. Why?

27. How is leaching carried out in case of low grade copper ores ?

28. Why is the extraction of copper from pyrite difficult than that from its oxide ore through reduction?

29. Write down the reactions taking place in different zones in the blast furnance during the extraction of iron.

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30. Name the process from which chlorine is obtained as a by product. What will happen if an aqueous solution of NaCl is subjected to electrolysis ?


31. Write short note on Zone Refining?

32. What metals are generally extracted by electrolysis process?

33. Discuss some of the factors which needs consideration before

deciding extraction of metals from its ore?

34. Indicate the temperature at which C can be used as reducing agent for

FeO?

35. Name Sulphide ore of Silver and Copper with the principal behind

their extraction?

36. Describe the method for refining Nickel?

37. How is Cast Iron is different from Pig Iron?

38. What is the significance of leaching in the extraction of the Aluminum?

39. Cu can be extracted by hydrometallurgy but not Zn, Explain?

40. Is it true that under certain condition Mg can reduce SiO2 and Si can

reduce MgO, what are those conditions?

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THE P BLOCK ELEMENTS

CHAPTER ‐7

WEIGHTAGE‐8

VERY SHORT ANSWER TYPE QUESTIONS: (ONE MARK EACH)

1. Draw the structure of XeF2 molecule.

2. Write one chemical reaction to show that chlorine gas can be obtained from bleaching powder.

3. Why is H2S more acidic than water .

4. Give reason for the following :‐

(a) PH3 is a weaker base than NH3.

5. Why is N2 not particularly reactive?

6. On being slowly passed through water PH3 forms bubbles but NH3 dissolves. Why is it so?

7. Why do nobles gases form compounds with fluorine and oxygen only ?

8. Why is HF the weakest acid among hydrohaloacids in spite of the fact that fluorine is most electronegative?

9. Which compound led to the discovery of the compounds of noble gas?

10. Explain why Oxygen is a gas while Sulphur is a solid ?.

11. Name one Ion whose central atom has the sp3d3 type of hybrid orbitals?

12. Noble gases are mostly chemically inert, why?

13. Why is bond dissociation energy of Fluorine molecule than Chlorine molecule?

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14. Draw the shape of SF6?

15. Which has larger bond angle H2S or H2O


16. How do you account for the reducing behavior of H3PO4?

17. Why phosphinic acid behaves as a monoprotic acid

18. How ammonia manufactured industrially?

19 How is nitrogen prepared in the laboratory?

20. Give the reason for bleaching action Cl2?

21. Illustrate how copper metal can give different products on reaction with HNO3.

22. Write main differences between the properties of white phosphorus and red phosphorus.

23. Write the conditions to maximize the yield of Sulphuric acid by contact process.

24. Sea is greatest source of some halogens .Comment

25. Name two poisonous gases which can be prepared from chlorine gas.

26. Why are fluorine and oxygen compound more aptly called as oxygen floride?

27. Why is HF is weakest acid among hydro haloacids?

28. Write two uses of elemental Silinium?

29. Define inert pair effect?

30. Give the disproportionation reaction of H3PO3

SHORT ANSWER TYPE QUESTIONS: (OF 3 MARKS EACH)

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31. How would you account that Hydrogen Floride is much less volatile than HCL?

32. Can PCl5 act as an oxidizing as well as reducing agent, justify?

33. Why does ammonia form hydrogen bond but PH3 does not?

34. Why is Helium used in diving apparatus?

35. Explain Fluorine forms only one oxo acids?

36. Why is dioxygen a gas but sulphur is solid?

37. White phosphorous is more reactive than red phosphorous, Explain?

38. Draw the structures of H3PO3 and XeOF4

39. Sugar get charred on addition of Conc Sulphuric Acid, Give reasons?

40. Why does nitrogen shows catenation properties less than phosphorous?

LONG ANSWER TYPE QUESTIONS: (OF 5 MARKS EACH)

41. Give reason reasons for reasons for each of the following observations:

(i) Sulphur vapour exhibits some paramagnetic behavior.

(ii) Despite lower electron affinity F2 is stronger oxidizing agent than Cl2.

(iii) Interhalogens compounds are more reactive than halogens.

(iv) Of the noble gases only xenon is known to form real chemical compounds.

(v) Nitrogen shows little tendency for catenation, whereas phosphorus shows a clear tendency for catenation.

42. (i) How is bleaching powder prepared ?Mention two its uses.

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(ii) Give two compounds of halogens in which the halogens display different positive oxidation states.

43 Justify the placement of O,S,Se,Te and Po in the same group of electronic cofiguratin ,oxidation state and hydride formation.

44. Mention three areas in which sulphuric acid plays an important role.

45 (i) Out of HI and HCl which has a weaker covalent bond and what effect has it on their acid strengths?

(ii) Draw the structure of peroxomonosulphuric acid.

46. (i) Why Hydrogen iodide os a stronger acid than hydrogen fluoride in aqueous solution?

(ii) Why the basic character among the hydrides of group 15 elements decreases with increasing atomic numbers?

47 (i) With the help of chemical equations ,explain in brief the principle of contact process for the manufacture of sulphuric acid.

(ii) How would you account that H3PO2 acts as monobaxic acid.

48 .Account for the following

(i) Neon is not known to form compounds

(ii) SbF5 is much more stable than BiF5.

49. What are interhalogen compouonds and why are they more reactive than corresponding moleculer halogens ?

50. Discuss the trends in chemical reactivity of group 15 elements?

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THE d AND f BLOCK ELEMENTS

CHAPTER‐8

WEIGHTAGE‐5 MARKS

VERY SHORT AHSWER TYPE QUESTIONS: (1 MARK EACH)

1. Why is the third ionization energy of Mg z=25 unexpectedly is high ?

2. In the transition series with an increase in atomic number the atomic radius does not changes very much Why it is so ?

3. Write the atomic no. of the element in which the filling of 3d subshell in the atom just starts ?

4. Name one ore of Mg and Cr?

5. Which is the most stable oxidation state among lanthanoids?

6. State the common characteristic of actinoids and lanthanoids which places them in the f block elements?

7. Write any two uses of pyrophoric alloys

8. Write the ionic equation representing the 0xidising properties of acidified KMnO4 solution

9 Why are the compounds of transition metals generally coloured?

10 Which property of the transition metal makes them good catalyst ?

11. Why is transition metals shows high enthalpy of hydration?

12. Give one use of Neobium?

13. What are coinage metals?

14. Name the metal that is refined by Monds process?

15. Why is Cu considered as a transition metal?

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16 Write chemical equation for the reactions involved in manufactured of potassium permanganate frpm pyrolusite ore ?

17 What is meant by Lanthanoids contraction .State one use of each of lanthanoids metals and their oxide ?

18 Describe with chemical equation the step involved in the preparation of potassium dichromate from sodium chromate?

19 What are interstitial compounds ? Mention their two important propertieis?

20 Explain why the first ionization energies of the element of the first transition series do not vary much with increase in atomic number ?

21 To what extent do the electronic configuration decide the stability of oxidation state in the first series of transition elements? Illustrate with example?

22 What are the different oxidation state exhibited by the lanthonoids?

23 How would you account for the irregular variations of first and second ionization enthalpies in the first series of transition elements?

24 What is meant by disproportionation of an oxidation states?Give an example

25 Discuss the general characteristics of 3d series of the transition element with special reference to their:‐

(i) Atomic sizes

(ii) Enthalpies of atomisation

26. Which is stronger reducing agent Cr2+ or Fe2+ and why?

27. Actinoid contraction is greater than Lanthanoid contraction and why?

29

28. Evaluate the magnetic moment of a divalent ion in aqueous solution of atomic No 25?

29. Explain why Cu2+ is stable in aqueous solution?

30. What is misch metal and mention its two use?


31. What are interstitial compounds and mentioned two important properties?

32. Which out of Se3+ and Cr3+ exhibits paramagnetism and why?

33. Explain why the first ionization energies of the element of the first series does not vary much with increase in atomic number?

34. Explain lanthanoid contraction?

35. What is meant by disproportationation reaction?

36 Explain the following :

(i) Transition elements tend to be unreactive with increasing atomic no. in the series

(ii) d block elements exhibits more oxidation states than f block elements

(iii) A green chromium compounds A on fusion with alkali gives yellow compounds B which on acidification gives an orange coloured compounds C . C on treatment with NH4Cl gives an orange coloured product D Which on heating decomposes to give back A Identify A B C and D.Write equation for reaction

37 (i) Give the balanced chemical equation of two reaction in which KMnO4 acts as an oxdising agent in the acidic medium

(ii) Chemistry of the actinoids is much more compliciated than that of lanthanoids .Why

30

38 Write the electronic configuration of the elements with the atomic no. 61, 91, 101 ,109.

39. Compare the chemistry of actinoids with that of lanthanoids with reference to :

(i) Electronic configuration

(ii) Oxidation state

(iii) Chemical reactivity

40 Name the members of the lanthanoids series which exhibits +4 oxidation states and those which exhibits +2 oxidation states try to correlate this type of behavior with electronic configuration of these elements .

LONG ANSWER TYPE QUESTION: (OF 5 MARK EACH)

41 What are alloys ? Name animportant alloy which contains some of the lanthanoids metals .Mention its uses.

42 Calculate the unpaired electrons in following gaseous ions : Mn 3+

,Cr+3,V+3,and Ti+3. Which one of these is the most stable in aquesous solution?

43 What is the basic differences between the electronic configuration of the transition and inner transition elements?

44 What are paramagnetic and ferromagnetic substances ?Account for the paramagnetic character of transition memtal compounds. How does the paramagnetic character of the bivalent ions of first transition metal series vary from Ti (z=22) to copper (z=29)?

45 How would you account for the following ?

(i) Only transition metals form complex compouonds with ligand such as CO.

31

(ii) Sc, the first member of first transition series does not exhibit variable oxidation state.

32

COORDINATION COMPOUNDS

CHAPTER –9

Weightage ‐3 marks:

VERY SHORT ANSWER TYPE QUESTIONS: (1 MARK EACH)

1. Write ionization isomers of [Co(NH3)5 Br] SO4?

2. Define co‐ordination number?

3. What is the difference between double salt and complex compound?

4. Name the type of isomerism that occurs in complexes in which both cations and anions are complex ions?

5. Name the metal present in chlorophyll and haemoglobin?

6. How many coordination sites are there in ethylene diamine?

7. Give an example of hexadentate ligand?

8. Give an example of chelate complexes?

9. Write the name of didentate ligand?

10. Give an example of ambidentate ligand?

11. Give the chemical formula for the compound potassium hexacynocobaltate (iii)?

12. How many isomers are there for octahedral complex [COCl2en(NH3)2]?

13. Write the formula of tetrachloro cuprate (ii) ion?

14. Give an example of hexadentate ligand?

15. How many coordination sides are there in ethylene diamine?

SHORT ANSWER TYPE: ( OF 2 MARKS EACH)

33

16. How is magnitude of ∆o affected by nature of ligand and oxidation state of metal ion?

17. Using the valence bond approach predict the shape and magnetic character of [Fe (CN)6 ]

‐3 ion?

18. Illustrate with an example of ionization isomerism in coordination compounds?

19. Describe briefly the nature of bonding in metal carbonyl?

20. How is stability of coordination compounds determined in aqueous solution?

21. What type of isomerism is exhibited by [Co(NH3)4Cl2]+ Br‐? Write the

structures of the possible isomers and the state of hybridization of the central metal atom?

22. Write all isomers of [Co(NH3)5NO2] Cl2

23. What is meant by hexadentate ligand? Give one example. How is such ligand useful for measuring hardness of water?

24. Mention applications of coordination compounds in following areas giving an example of each:‐

(a) Analytical Chemistry

(b) Extraction of metals

25. Using valence bond theory explain the bonding in [Cr(H2O)6]3+ . (At No

Cr = 24)

26. Write the state of hybridization and the oxidation state of the central atom in each of the following species :‐

(a) Cis – [Co(NH3)4Cl2]+

(b) [PtCl3(C2H4)]‐ (Atomic Number of Pt = 78)

34

27. Using the valence bon approach, deduce the shape and magnetic behavior of [Cr(NH3)6]

3+ ion

28. Predict the shape and magnetic character of each of the following :‐

(a) [Cr (NH3)6]3+

(b) [Cr (CO)6] (Atomic number of Cr = 24)

29. Write the structures of a pair of complexes showing geometrical isomerism?

30. In a complex ion : [Co(NH3)3(H2O)2 Cl]+

(a) Identify the ligand’s formula and the change on each one of them

(b) Write the geometry of complex ion

SHORT ANSWER TYPE: ( OF 3 MARKS EACH)

31. Illustrate with a example ionization isomerism in coordination compounds?

32. How is stability of coordination compounds is determined in aqueous solution?

33. Explain crystal field theory?

34. Explain Werner’s theory of coordination chemistry?

35. Define secondary valency with examples?

36. Define chelating ligand?

37. What do you mean by linkage isomerism, explain with examples?

38. Give an example of linkage and ionization isomerism?

39. Write the postulates of Valence Bond Theory?

40. What is meant by hexa dentate ligands.

35

HALOALKANES AND HALOARENES

CHAPTER ‐10

Weightage‐4 marks


1. Name the instrument used for measuring specific rotation.

2. What are meso compouonds

3. What is meant by resolution ?

4. What is meant by specific rotation ?

5. What is meant by dhirality of molecules?

6. An alkyl halide having molecular formula C4H9Cl is optically active .What is its structure?

7. What is retention ?

8. What is order for SN2 mechanism ?

9. What is meant by plane polarized light ?

10. What is meant by plane polarized light ?

11. Inversion is associated with type of mechanisms?

12. What are diastereomers?

13. Why is Sulphuric Acid not used during the reaction of alcohols with KI?

14. Out of C6H5CH2Cl and C6H5CHCIC6H5, which is more easily hydrolysed by KOH?

15. What is meant by chirality of molecule?

SHORT ANSWER TYPE QUESTIONS (2 MARKS EACH)

36

16. What is meant by axis of Symmetry?

17. How May methyl bromide be preferentially converted to methyl cyanide and methyl isocynide?

18. How can iodoform be prepared from ethanol ?

19. Starting from methyl iodide ,how will you prepare :‐

(i) nitromethane and

(ii) methyl nitrite ? Write the complete reaction involved.

20. Describe laboratory preparation of Chloroform .Why is it strored in dark coloured bottles? Give four main uses of chloroform.

21. How can enantiomers different from diastereomers? Give one example of each.

22. Convert:

(i) Benzene to p‐nitrochlorobenzene

(ii) Choropropane to propanol

23. What is an electrophile ? Give two examples of electrophilic substitution reactions.

24. What happens when propene is treated with HBr in prescence of peroxide?

25. Primary alkyl halide C4H9Br (A)Reacted with alcoholic KOH to give compound (B).Compound B is reacted with HBr to give C which is an isomer of A.When A is reacted with sodium metal it gives compound D C8H18 that was different from the compound formed when n‐ butyl bromide is reacted with sodium.Give the structural formula of A and write the equations for all the reactions.

26. Explain why the dipole moment of chlorobenzene is lower than that of cyclohexyl chloride ?

37

27. Explain why Grignard reagent should be prepared under anhydrous conditions.

28. Arrange the compounds of each set in order of reactivity towards SN2 displacement:‐

(I) 2Bromo‐2methylbutane , 1‐bromopentane ,2‐Bromopentane

(II) 1 Bomo‐3‐methyl butane , 2‐Bromo‐2‐methyll butane, 3‐Bromo‐2 methyl butane

29. An alkyl chloride A on retion with magnesium in dry ether followed by treatment with ethanol gave 2‐methylbutane.Write all the possible structures of A.

30. The nucleophilic substitution of primary alkyl chlorides with sodium acetate is catalysed by sodium iodide.Explain why?

SHORT ANSWER TYPE QUESTIONS (3 MARKS EACH)

31. p‐Methoxybenzyl bromide reacts faster than p‐nitrobenzyl bromide with ethanol to form an ether product.Explain why.

32. How will you distinguish between :‐

(i) Propan‐1‐ol and Propan‐2‐ol?

(ii) Methylamine (CH3NH3) and Dimethylamine [(CH3)2NH3]

33. Write the structures of main products of :–

(i) Chlorination of benzene in presence of UV light?

(ii) Propene is treated with HBr in presence of benzoyl peroxide?

34. The nucleophilic substitution of primary alkyl chloride with sodium acetate is catalysed by sodium iodide. Why?

35. What happens when :‐

38

(i) N‐butyl chloride is treated with alcoholic KOH?

(ii) Bromobenzene is treated with Mg in the presence of dry ether?

(iii) Cholrobenzene is subjected to hydrolysis/

36. Write the equation for preparation of 1‐iodobutane from :‐

(i) 1‐butanol

(ii) but‐1‐ene

37. An excess of methyl magnesium iodide reacts with 0.6g of an organic compound C3H6O3 to evolve 295.7 ml of methane gas at STP? Calculate the number of active hydrogen atoms in the molecule of organic compound?

38. Write chemical equations and reaction conditions for the conversion of :‐

(i) Ethene to ethanol

(ii) Propene to 1‐propanol

(iii) Chloroform to ethane

39. Explain why :‐

(i) Vinyl Chloride is unreactive in nucleophilic substitution reactions?

(ii) neo‐pentyl bromide undergone nucleophilic substitution reaction are very slowly?

(iii) 3‐bromocyclohexane is more reactive than 4‐bromocyclohexane in hydrolysis with aqueos NaOH?

40. Which of the following compounds will give positive iodoform test :‐

(i) Butan‐1‐ol

39

(ii) Butan‐2‐ol

(iii) Tert‐butanol


41. How will you bring about the following conversion :‐

(i) Ethene to Bromethene

(ii) Toulene to Benzene

(iii) Ethanol to but‐1‐yne

(iv) Propene to propyne

(v) Benzene to biphenyl

42. Explain :‐

(i) What is optical activity ? What are the necessary and sufficient conditions for a molecule to exhibit optical activity?

(ii) What is optical rotation? Name the instrument used to measure optical rotation. How is optical rotation different from specific rotation?

43. What are nucleophilic substitution reactions ? What type of alkyl halide undergoes nucleophilic substitution reaction via SN1 and SN2 mechanisms? Describe the mechanism and stereochemistry of the reaction?

44. Explain :‐

(i) Differential between meso compound and racemic mixture. Give one example of each/

(ii) Give optical isomers of 2‐chlorobutane

(iii) What is meant by retention of configuration? Illustrate with examples?

40

ALCOHOLS, PHENOLS AND ETHERS

CHAPTER‐11

Weighatge‐4 marks

VERY SHORT ANSWER TYPE QUESTION(1 MARK EACH)

1 Mention two uses of methanol?

2 Why o‐nitrophenol has lower boiling point than p‐ nitrophenol.

3 How is acetone obtained from 2‐bromopropane?

4 Give chemical test to distinguished between phenol and benzoic acid.

5 Write one example of each: nucleophile and electropphile.

6 In absence of kerosene oil can we store sodium metal in diethyl ether or ethyl alcohol or anhydrous hexanol ?

7 How is phenol obtained from aniline ?

8 How is ethanoic acid industrially obtained from ethanol?

9 Mention an industrial product manufactured from methanol.

10 How many sigma bonds are present in 3‐methyl phenol?

11 Write chemical reaction for the preparation of phenol from chlorobenzene .

12 Give reason for the higher boiling points of ethanol in comparison to methoxymethane.

13 What happens when Cumene is treated with oxygen and the product is hydrolysed with dilute acid.

14 Name a compound which is used as antiseptic as wellas disinfectant .

41

15 What happens when propanaol is treated with HCl in prescence of anhydrous ZnCl2


16 How would you account for the following :

(i) Phenols are much more acidic than alcohols.

(ii) The boiling points of ethers are much lower than those of the alcohols of comparable molar masses.

17 Give an illustration of Reimer Tiemann reaction.

18 What happens when ethanol is heated with concentrated sulphuric acid at 453 K? Explain the mechanism of this reaction.

19 How are the following conversions carried out ?

(i) Phenol to Tolune

(ii) Ethanol to 1,1dichloroethane.

20 While separating a mixture of ortho and para nitrophenols by steam vikatuke,Give reasons?

21 Describe the mechanisms by which the hydroxyl group attached to an aromatic ring is more acidic than the hydroxyl group attached to an alkyl group .How does the presence of a nitro group in phenol affect its acidic character?

22 Of ethanol and n‐ propanol which one gives iodoform test and why does the other one not do so?

23 Phenol is a very weak acid.What substitutions in the molecule can make it astronger acid and a weaker acid and why?

24 Why is it that phenol is acidic and hexanol is neutral towards a solution of NaOH?

25 Nitration of phenol gives only ortho and para products .Give reasons.

42

26 What is Williamsons synthesis ? What type of compounds are prepared by this reaction?

27 Explain why cleavage of phenyl alkyl ether with HBr always gives phenol and alkyl bromide.

28 Explain mechanism of ethanol to ethane.

29 Alcohols are comparatively more soluble in water than hydrocarbons of comparable molecular masses.Explain this fact.

30 Preparation of ethers by acid dehydration of secondary or tertiary alcohols is not a suitable method .Give reason.


31. Write IUPAC names of the following :‐

(i) C6H5OC2H5

(ii) C6H5OC7H15

32. Write the structures of the major products expected from the

following reactions :‐

(i) Mononitration of 3‐methylphenol

(ii) Dinitration of 3‐methylphenol

33. Give the structures of the products you would expect when each of

the following alcohol reacts with :‐

(i) HCl‐ZnCl (ii) HBr (iii) SOCl2

34. How will you synthesize :‐

(i) 1‐phenylethanol from a suitable alkene?

(ii) pentan‐1‐ol using a suitable alkyl halide?

43

35. Give the structures and IUPAC name of the products expected from

the following reactions :‐

(i) Catalytic reduction of butanal

(ii) Hydration of Propene in the presence of dilute sulphuric acid

36. Name the reagents used in the following reactions :‐

(i) Oxidation of a primary alcohol to carboxylic acid

(ii) Bromination of phenol to 2,4,6 tribromo‐phenol

37. Give two reactions that show the acidic nature of phenol. Compare

acidity of phenol with that of ethanol ?

38. Draw the structures of the compounds whose IUPAC names are :‐

(i) 2, 3‐Diethylphenol

(ii) 1‐Ethoxypropane

39. Write the equation of the reaction of hydrogen iodide with

(i) 1‐Propoxypropane (ii) Benzyl ethyl ether

40. Explain the fact that in aryl alkyl ethers

(i) the alkoxy group activates the bezene ring towards the

electrophilic substitution?

(ii) Directs the incoming substituent’s to ortho and para positions in

benzene ring?

44

ALDEHYDES, KETONES AND CARBOXYLIC ACIDS

CHAPTER ‐12

Weightage‐6


1 How is aminoethane obtained from ethanol ?

2 Mention one important tests to distinguish between:

3 Formic acid and Acetic acid

4 Mention one important use of methanoic acid.

5 What product is obtained when ethyl benzene is oxidized with alkaline KMnO4.

6 What happens when ethanoyl chloride is subjected to Rosenmund reduction?

7 When propanone is subjected to Wolf‐Kisher reduction, what product will be obtained ?

8 Which type of aldehydes undergo aldol condensation?

9 Why does acyl chloride have lower boiling point than corresponding acids?

10 Name two important uses of formalin.

11. Write the IUPAC name of CH3COCH2COCH3 ?

12. How is acetone obtained from ethanol?

13. Mention one important use of methanoic acid

14. What product is obtained when ethyl benzene is oxidized with alkaline KMnO4 ?

45

15. Write chemical tests to distinguish between Formic acid and acetic acid?

SHORT ANSWER TYPE QUESTIONS : (2 MARKS EACH)

16 Give simple chemical tests to distinguish between the following pairs of compounds:

(i) Acetophenone and Benzophenone

(ii) Benzaldehyde and Acetophenone

17 How will you bring about the following conversions in not more than two steps?

(i) Propnone to propene

(ii) Ethanol to 3‐ Hydroxybutanal

18 Explain during the preparation of esters from a carboxylic acid and an alcohol in the presence of an acid catalyst , the water or the ester should be removed as soon as it is formed.

19 Why is carboxyl group in benzoic acid meta directing ? Support your answer with two examples.

20 Draw the structure of a carbonyl group and indicate clearly

(i) The hybridized state of carbon

(ii) The sigma and pie bonds present

21 Describe simple chemical tests to distinguish between the following pairs of compounds;

Diethyl ether and Propanol

22 Write structural formulae and names of the four possible aldol condensation products from propanal and butanal.In each case indicate which aldehyde acts as nucleophile and which as electropphile.

46

23 Although phenoxide ion has more number of resonating structures than carboxylate ion carboxylic acid is a stronger than phenol.Why?

24 Draw the structures of the following compounds :

(i) 3‐methylbutnal

(ii) 4‐cholropentane‐2one

25 Two moles of organic compound A on treatment with a stron base gives two compounds B and C.Compound B on dehydrogenation with Cu gives A while acidification of C yields carboxylic acid D having molecular formula of CH2O2.Identify the compouonds A,B,C, and D.

26 How will you convert ethanol into the following compouonds?

(a) Buta‐2‐one

(b) butan‐1‐ol

27 Write chemical reactions to affect the following transformations:

(i) Butanol to butanoic acid

(ii) Benzyl alcohol to phenylethanoic acid

28 Draw structures of the following derivatives

(i) Cyclopropanone oxime

(ii) Acetaldehydedimethylacetal

29 Name the following compounds to IUPAC nomenclature

(i) CH3CH2COCH2CH2Cl

(ii) CH3COCH2COCH3

30 Give reason for the following Sodium bisulphate is used for the purification of aldehydes and ketones.

SHORT ANSWER TYPE QUESTIONS : (3 MARKS EACH)

47

31. Give chemical tests to distinguish between the following pair of compounds :‐

(i) Propanal to Propanone

(ii) Benzaldehyde to Benzoic acid

32. Write chemical equation to illustrate each of the following reaction :‐

(i) Acylation reaction

(ii) Rosenmund reaction

33. (i) Most aromatic acids are solids while acetic acid and others of the series are liquids?

(ii) Why ketones are less reactive towards nucleophiles than aldehydes?

34. State the sequence of steps to obtain :‐

(i) Acetophenone from benzene

(ii) Acetone from acetyl chloride

35. State :‐

(i) Why benzaldehyde does not undergo aldol condensation?

(ii) How an acid amide may be converted to the parent acid?

36. An organic compound ‘A’ (molecular formula C3H6O) is resistant to oxidation but forms a compound ‘B’ (C3H8O) on reduction. B reacts with HBr to form a bromide C which on treatment with alcoholic KOH forms an alkene D (C3H6) . Deduce the structures of A. B. C. D

37. Giving an example of each with necessary reaction conditions :‐

(i) Tollen’s test

(ii) Fehling’s test

48

(iii) Friedal Crafts Reaction

38. Carboxylic acid do not give reaction of aldehydes and ketones. Why?

39. Distinguish between :‐

(i) Acetaldehyde and benzaldehyde

(ii) Propanol and Propanone

40. Why pH reaction should be carefully controlled while preparing ammonia derivatives of carbonyl compound?


41 Predict the product formed when cyclohexanecarbaldehyde reacts with following reagents.

(i) PhMgBr and then H3O

(ii) Tollens reagent

(iii) Semicarbazide and weak acid

(iv) Excess ethanol and acid

(v) Zinc amalgam and dilute hydrochloric acid

42 (i) Describe the preparation of acetic acid from acetylene.

(ii) How can the following be obtained from acetic acid :

(a) Acetone?

(b) Acetaldehyde?

43 Why is the boiling point of an acid anhydride higher than the acid from which it is derived?

44 What is meant by the following terms/Give an example in each case

(a) Cyanohydrin

49

(b) Semicarbazide

(c) Hemiacetal

(d) Ketal

(e) 2,4‐DNP

45 Give plausible explanation for each of the following :

(i) Cyclohexanone forms cyanohydrins in good yield but 2,2,6‐tri methylcyclohexanone does not.

(ii) There are two –NH2 groups in semicarbbazide. However onlyone is involved in the formation of semicarbazones.

(iii) During the preparation of esters from a carbosylic acid and an alcohol in the presence of an acid catalyst the water or the ester should be removed as soon as it is formed.

50

ORGANIC COMPOUNDS CONTAINING NITROGEN

CHAPTER‐13

Weightage ‐‐4


1 Why do amines react as nucleophiles ?

2 Mention one commercial use of N,N‐Dimethylaniline (DMA)

3 Give a chemical test to distinguish between aniline and ethylamine.

4 How is m‐nitroaniline obtained from nitirobenzene?

5 Why are primary amines higher boiling than tertiary amines?

6 How is aniline obtained from benzoic acid?

7 Write the chemical equations for the following chemical reactions: A primary amine is prepared from a primary alkyl halide.

8 How is the basic strength of aromatic amines affected by the presence of an electron releasing group on the benzene ring?

9 What is the structural formula of the zwitter ion formed from alanine?

10 How is acetanilide prepared from aniline?

11 An organic compound A having molecular formula C2H7N on treatment with HNO2 gave an oily yellow substance.Identify A .

12 Write the chemical reaction occurring in the preparation of fluorobenzene from aniline.

13 Account for the following :

Ammonolysis of alkyl halide does not give a corresponding amine in pure state.

14 Write one chemical reaction for carby;amine test.

51

15 Name the compound formed by coupling reaction of 4‐aminobenzenesulphonic acid and N,N‐dimethylbenzenamine and give its one use.


16 Give reasons :

(i) Methyl amine is a stronger base than ammonia.

(ii) Reactivity of –NH2 group gets educed in acetanilide .

17 Illustrate the following with an example of reaction in each case;

(i) Sandmeyer reaction

(ii) Coupling reaction

18 Amino group is o,p directing for aromatic electrophilic substitution .Why does aniline on nitration gives a substantial amount of m‐ nitroaniline?

19 Write reactions of the final alkylation product of aniline with excess of methyl iodide in the presence of sodium carbonate solution.

20 Why cannot aromatic primary amines be prepared by Gabriel phthalimide synthesis?

21 Write chemical reaction of aniline with benzoyl chloride and write name of the product obtained .

22 Explain Diazonium salts of aromatic amines are more stable than those of aliphatic amines.

23 How will you convert:

(i) Nitromethane into dimethylamine

(ii) Propanoic acid into ethanoic acid?

52

24 Describe tests to distinguish between Secondary amine and tertiary amines .

25 Before reacting aniline with HNO3 for nitration it is converted to acetanilide.Why is this done and how is nitroaniline obtained subsequently?

26 Why does bromination of aniline, even under very mild conditions give 2,4,6‐tribromoaniline instantaneously?

27 Out of ethylamine and ethyl alcohol which has higher boiling point and why?

28 Give reasons for the following:

Sulphanilic acid I insoluble in water but is soluble both in aqueous bases and aqueous mineral acids taken separately.

29 Explain why the amino group in aniline acts as a powerful activator and ortho and para director towards electrophilic substitution reaction.

30 Condensation of aniline and benzaldehyde gives compound A that is hydrogenated to give B.Identify A and B.


31. Give reasons :‐

(i) Methylamine is a stronger base than ammonia?

(ii) Reactivity of –NH2 group gets reduced in acetanilide?

32. Write short notes on :‐

(i) Coupling reaction

(ii) Ammonolysis

53

33. Complete the following reaction :‐

(i) C8H5NH2 + CHCl3 + alc KOH

(ii) C6H5N2Cl + C2H5OH

34. How will you convert the following :‐

(i) Methanol to ethanoic acid

(ii) Ethanamine into methanamine

35. Write reaction of the final alkylation product of aniline with excfess of

methyl iodide in the presence of sodium carbonate solution?

36. How will you convert 4‐nitrotoulene to 2‐bromobenzoic acid?

37. Give one chemical test to distinguish between the following pair of

compounds :‐

(i) Aniline and benzylamine

(ii) Aniline and N‐methylaniline

38. Out of ethylamine and ethyl alcohol which has higher boiling point and

why?

39. Describe the following process with examples :‐

(i) Diazotisation

(ii) Acetylation

40. Before reacting aniline with HNO3 for nitration, it is converted to

acetanilide. Why is this done and how is nitroaniline is obtained?

54

BIOMOLECULES

CHAPTER ‐14

WEIGHTAGE ‐4

VERY SHORT ANSWER TYPE QUESTION(1 MARK EACH)

1. Why is cellulose in our diet not nourishing ?

2. Under what conditions does each protein take shape that is energetically most stable ?

3. In what sense are the two strands of DNA not identical but complementary ?

4. Menation two clases of niotrogen containing bases found in nucleotides ?

5. Name the purines present in DNA

6. Define native state in reference to protein?

7. Why are carbohydrate generally optically active?

8. Give examples of anomers ?

9. Name the base that is found in nucleotide of RNA only?

10. What are amino acid ?

11. What type of bonding occurs in alpha helix configuration ?

12. Name simplest carbohydrate containing 3 carbon atom ?

13. What structural difference is there between alpha glucose and beta?

14. Which type of bonds are responsible for secondary structure of protein?

15. What products would be formed when a nucleotide from DNA containing thymine is hydrolyses ?

55


16. Why cannot vitamin C be stored in our body?

17. Enumerate the reaction of d glucose which cannot be explained by its open chain structure?

18. State two differences between globular and fibrous protein?

19. What are essential and non essential amino acids?

20. Explain the term mutarotation, giving an example?

21. Describe two important functions of nucleic acids?

22. How do you explain the absence of aldehyde group in penta acetate glucose?

23. The melting points and the solubility in water of amino acids are generally higher than the corresponding halo acids why explain?

24. What are reducing and non reducing sugar?

25. Draw open chain structure of aldopentose and aldohexose?

26. What are common types of secondary structure of proteins ?

27. How do you explain the amphoteric behavior of amino acids?

28. Write the important structural and functional differences between DNA and RNA?

29. Define vitamins and state their classifications?

30. Name the main diseases caused due to lack of Vitamin and its source in A, B & C?


31. State difference between globular and fibrous proteins. Give one example of each?

56

32. State the difference between the following pairs :‐

(a) ά –Helix and β Pleated sheet structures

(b) Primary and secondary structures of protein

33. Give the products of hydrolysis of (a) maltose (b) Lactose

34. What happens when D‐Glucose is treated with the following reagents :‐

(a) HI (b) Bromine water (iii) NH3

35. Write four characteristics features of enzymes. Name a disease which is caused by the deficiency of a particular enzyme?

36. Name three major classes of carbohydrates and give one example of each class/

37. Define :‐

(a) Co‐enzymes

(b) Mutation in biomolecules

38. Define vitamins and state their classification. List two vitamins of each classification?

39. What do you mean by renaturation and denaturation of proteins?

40. Define the following as related to proteins :‐

(a) Peptide linkage

(b) Primary structure

57

LONG ANSWER TYPE QUESTIONS(OF 5 MARKS EACH)

41. Write down the structures of the product formed when D‐Glucose is treated with :‐

(a) Hydroxyl amine

(b) HI

(c) Ammonical silver nitrate

42. How are harmones and vitamins different in respect of their sources and functions?

43. What are complimentary bases, draw structures to show hydrogen bonding between adenine and thymine?

44. What type of linkage is responsible for primary structure of protein, explain with example?

45. Name the three major classes of Carbohydrates and give the distinctive characteristic of each class?

58

POLYMERS

CHAPTER 15

WEIGHTAGE – 3 MARKS

VERY SHORT ANSWERS (1 MARK EACH)

1. Explain the difference between Buna‐N and Buna – S?

2. Define the term polymerization?

3. What are polymers?

4. Define homopolymer?

5. Write monomers of Bakelite?

6. Urea and Formaldehyde are the monomers of which polymer?

7. Write the name and structure of one of the common initiater used in free radical addition polymerization?

8. Give monomers of Glyptal?

9. Write the structure of monomer used in the preparation of Teflon?

10. How does vulcanization change the character of natural rubber?

11. Why are the numbers 66 and 6 put in the names of nylon‐66 and nylon‐6?

12. Draw the structure of the monomer of Nylon‐6?

13. Define copolymer?

14. Give example of Biodegradable polymer?

15. Define Chain growth polymerization?

SHORT ANSWERS QUESTIONS: ( OF 2 MARKS EACH)

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16. What are bio degradable polymers?

17. What is the difference between thermostatic and thermoplastic polymers?

18. Write formula of monomers of polythene and Teflon?

19. Write the structure of monomer used In Buna‐N?

20. What are elastomers?

21. How are polymers are classified in different categories?

22. How is terrylene synthesized?

23. Name the four catergory in which polymers have been classified on the basis of magnitude of forces present in them?

24. How is Bakelite made and what is its measure use?

25. What are the different ways of initiating addition polymerization?

26. Give one example for each differentiate between thermostatic and thermoplastic polymers?

27. How does the presence of double bond in rubber molecules influence their structure and reactivity ?

28. What are natural and synthetic polymers?

29. How can you differentiate between addition and condensation polymerization?

30. How is Decron obtained from ethylyne glycol and terphthalic acids?

SHORT ANSWERS QUESTIONS: ( OF 3 MARKS EACH)

31. Explain the term copolymerization?

32. Discuss the main purpose of vulcanization of rubber?

33. What are biodegradable polymers and give two examples?

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34. Write the names and the structures of the monomer units of polystyrene?

35. Comment on the structural difference between thermoplastics and thermosetting polymers/

36. What are elastomers? Write the chemical equation to represent the preparation of Buna‐S?

37. Write equation used for the synthesis of :‐

(a) Terylene

(b) Neoprene

38. How can you differentiate between addition and condensation polymerization?

39. How is Dacron obtained from ethylene glycol and terephtalic acid?

40. Write the monomers of Nylon‐2, Nylon‐6 and PHBV? Give their uses also?

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CHEMISTRY IN EVERYDAY LIFE

CHAPTER 16

WEIGHTAGE – 3 MARKS

VERY SHORT ANSWER (1 MARK EACH)

1. Name two narcotics which are used analgesic?

2. Why is ethanol is added to soap?

3. What are the used of compounds which is obtained from the bark of willow tree?

4. What type of drug penicillin is ?

5. Name the chemicals responsible for Dettol?

6. Define soap?

7. Why is bithional added to the toilet soaps/

8. Name one medicinal compound used to treat hypertension?

9. What are food preservatives?

10. Define the term Chemotherapy?

11. Why do soaps not worked in hard water?

12. Name a substance which can be used as antiseptic and disinfectant?

13. What type of drug is chloramphenicol?

14. Name one medicinal compound used to treat (i) Hypertension (ii) Body Pain

15. Write the IUPAC name of aspirin?

SHORT ANSWER QUESTIONS: ( OF 2 MARKS EACH)

62

16. Name a drug used in mental depression?

17. Write down the formulae of Parecetamol and what is it used for?

18. What are antipyratic medicine and name one of them?

19. Name a broad spectrum antibiotics and state two diseases for which it is prescribed?

20. What do you understand by broad spectrum antibiotic?

21. Describe the functions of antibiotic and antisceptic?

22. Why do we require artificial sweetening agents?

23. Why do we need to classify a drug in different ways?

24. Which forces are involved in holding the drugs to active sides of Drugs?

25. Why are cimetidine and ranitidine better antacids than Sodium hydrogen carbonate and magnesium hydroxide?

26. What is tincture of iodine?

27. How are syenthetic detergents better than soaps?

28. Explain the cleansing action of soap?

29. Why should not medicines be taken without consulting doctors?

30. Why do soaps do not work in hard water?

SHORT ANSWER QUESTIONS: ( OF 3 MARKS EACH)

31. Mention one important use of :‐ (i) Equanil (ii) Sucralose

32. Name a broad spectrum antibiotic and state two diseases for which its prescribed?

33. Describe with examples :‐

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(a) Preservatives

(b) Biodegradables detergents

34. Give three examples of Sulpha drugs and write their main uses?

35. Write the formula of paracetomol and its uses?

36. What are antipyretic medicines and name anyone of them?

37. Why paracetomol is is preferred over aspirin?

38. Give two examples of organic compounds used as antiseptics?

39. Name the action of the following on human body :‐ (a) Aspirin (b) Paracetomol (c) Peniciliin

40. Why do we require artificial sweetening agents?

chemistry

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