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SECTION - I (40 marks)Compulsory : Attempt all questions from this section.

Question 1.(a) Choose the corresponding letter for the correct answer from the choices A,

B, C and D.(i) On moving from left to right in a period, the metallic character of elements

A) increases B) decreasesC) remains the same D) varies irregularly

(ii) Which of the following contains maximum number of molecules?A) 4g of O2 B) 4g of NH3C) 4g of SO2 C) 4g of CO2

(iii) The ions present at the anode during electrolysis of molten lead bromide areA) Pb2+ B) Br2- ionsC) Br- ions D) none of these

(iv) Which of the following has double bond between two atoms?A) H2 B) O2C) N2 D) PH3

(v) The equation for the reaction between magnesium and dilute sulphuric acidis shown.Mg + H2SO4 MgSO4 + H2

Mol. wt of MgSO4 is 120g.Which mass of magnesium sulphate will be formed if 12 g of magnesium isreacted with sulphuric acid.A) 5g B) 10gC) 60g D) 50g

(vi) Which property is shown by all metals?A) They are extracted from their ores by heating with carbon.B) They conduct electricity.C) They form acidic oxides.D) They react with hydrochloric acid to form hydrogen.

(vii) Which of the following is an unsaturated compound?A) C6H14 B) C3H7OHC) CH3OH D) C4H8

(viii) A salt which in solution gives a bluish white precipitate with NaOH solutionand a white precipitate with BaCl2 solution isA) CuSO4 B) FeSO4C) Fe2(SO4)3 D) CuCl2

(ix) The gas law which relates the volume of a gas to moles of the gas isA) Avogadro’s law B) Gay-Lussac’s lawC) Boyle’s law D) Charle’s Law

(x) Formation of chloroform from methane and chlorine is an example ofA) Addition B) DehydrationC) Substitution D) Elimination

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(b) (i) A gas cylinder contains 24 × 1024 molecules of nitrogen gas. If theAvogadro’s number is 6 × 1023 and the relative atomic mass of nitrogen is14, calculateA) Mass of nitrogen gas in the cylinder.B) Volume of nitrogen at STP.

(ii) 3000 cc of oxygen was burnt with 600 cc. of ethane (C2H6). Calculate thevolume ofA) Carbon dioxide formedB) Unused oxygen

(c) Name the following:(i) A gas evolved when a white crystalline solid is warmed with Ca(OH)2

solution which turns moist litmus paper blue.(ii) A reagent that can distinguish between ethene and ethyne.(iii) A gas that can be oxidised to sulphur.(iv) The amount of substance containing particles equal to Avogardro’s number.(v) A complex salt used for electroplating an article with silver.

(d) State your observations for the following cases:(i) Conc. sulphuric acid is added to sugar.(ii) Copper is heated with conc. nitric acid.(iii) Ammonia is burnt in oxygen.(iv) Lead carbonate is heated and then cooled.(v) Potassium permanganate is heated with conc hydrochloric acid.

(e) Write equations for the following reactions:(i) Excess ammonia reacts with chlorine.(ii) When sulphur reacts with conc. nitric acid.(iii) Lead (IV) oxide reacts with conc. hydrochloric acid.(iv) Nitrogen dioxide and water in presence of oxygen.(v) Sodium thiosulphate reacts with dilute hydrochloric acid.

(f) Write the I.U.P.A.C. names of the following compounds.(i) (ii)

(iii) (iv)

(v)

(g) The following diagram illustrates electro refining of copper. Answer thefollowing questions based on diagrammatic illustration.

[2]

[3]

[5]

[5]

[5]

[5]

[5]

H

H

CH

H

O

C H

H

CH

H

H

CH

H

COH

H

CH

C2H5 O C2H5

H

H

CH

H

C

H

C H

H

C

H

H

H

CH

CH3

CH

H

C HH

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(i) What is the cathode made up of?(ii) Which is the electrolyte used?(iii) Give the reaction occurring at the anode?(iv) Name any other two metals which can also be refined by this method.(v) “Slime is left during electro refining”. What is this slime.

SECTION - II(Attempt any four questions)

Question 2.(a) Study the diagram illustrating the manufacture of sulphuric acid given

below. Give equations for following conversion identify A, B, C & D.

(b) From the metals copper, iron, magnesium, sodium and zinc, select a differentmetal in each case which :

(i) Can form 2+ and 3+ ions.(ii) Has a hydroxide that reacts with both acids and alkalis.(iii) does not react with cold water but reacts with steam reversibly when heated.

(c) Choosing only substances from the list given in the box below, write equationsfor the reactions which you would use in the laboratory to obtain:(i) Sodium sulphate (ii)Iron (II) sulphate (iii) Zinc carbonate

Question 3.(a)

In the table given above A, B, C and D are elements. Given B is an inert gas(not helium), what type of bonding would take place between(i) A and C (ii) A and D

[4]

[3]

[3]

[2]

Dilute sulphuric acid Iron Copper carbonateSodium Sodium carbonate Zinc

Cu2+Cu2+

Battery

Nitricacid

Element Atomic number

A Z – 1

B Z

C Z + 1

D Z – 1

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B

DE

H2SO4

FeS

SO2

F sulphur Oleum

C

SO3

G

A

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(b) State the anion present in each of the following solutions A, B, C and D.(i) An aqueous solution of ‘A’ on heating with dilute mineral acid, give a

gas which turns lead acetate paper silvery black.(ii) An aqueous solution of ‘B’ reacts with barium nitrate solution to give a

white precipitate insoluble in dil. nitric acid.(iii) The solution ‘C’ reacts with con. sulphuric acid on heating to give acid

vapours which on heating with copper turnings gives a gas which turnspotassium iodide solution brown.

(iv) The substance ‘D’ reacts with dilute sulphuric acid on heating to acolourless,odourless gas which turns lime water milky.

(c) From the list of the substances given below:Washing soda, Ferric chloride, Sodium chloride Hydrogen chloride. Name thecompound which would:(i) Gains weight on exposure to air.(ii) Loses weight on exposure to air.

(d) Draw the electron dot diagram of a molecule of(i) Carbon tetrachloride (ii) Water

Question 4.(a) Write the equations for the following laboratory preparations:(i) Ethane from sodium propionate(ii) Ethene from iodoethane(iii) Ethene from ethyl alcohol(iv) Ethyne from calcium carbide(v) Ethanoic acid from ethanal

(b) (i) Draw the structural formula of the final product when ethane reacts withexcess chlorine in the presence of diffused sunlight.

(ii) What would you observe when ethyne is passed through ammoniacal silvernitrate solution?

(iii) X and Y are successive members of the same homologous series. If themolecular mass of X is 60, what is the molecular mass of Y.

(iv) What is glacial acetic acid?(v) Define catenation.

Question 5.(a) This question is based on laboratory preparation of Hydrogen chloride gas.

See the diagram below and answer the following question.

(i) Write the chemicals ‘A’ and ‘B’ used in the reaction.

[4]

[2]

[2]

[5]

[5]

[5]

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B

DC

A

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[2]

[3]

[5]

[2]

[3]

[5]

[3]

[2]

(ii) Write the balanced chemical equation for the reaction taking place in the above process.

(iii) What happes when the glass rod dipped in ammonia is brought near themouth of jar ‘C’.

(iv) What is the use of conc. sulphuric acid in ‘D’.(v) Why Nitric acid is not used in preparation of Hydrogen chloride.

(b) From the equation(NH4)2Cr2O7 Cr2O3 + 4H2O + N2 Calculate the(i) Volume of nitrogen at STP evolved when 63 g of ammonium dichromate is

heated.(ii) Mass of chromium (III) oxide formed at the same time.

(N = 14, H= 1, Cr = 52, O = 16)

(c) A gaseous hydrocarbon contains 82.6% carbon. If the vapour density ofhydrocarbon is 29, calculate its molecular formula. (C = 12, H =1)

Question 6.(a) Name the following :(i) a non-metal which is in liquid state.(ii) a non-metal which is lustrous and sublimes on heating.(iii) a metal which is a poor conductor of electricity.(iv) method used to concentrate sulphide ores.(v) a non-metal which is ductile.

(b) Write a balanced equations for :(i) The reaction of magnesium nitride with warm water.(ii) The reaction of dilute nitric acid with zinc.

(c) (i) Account for the yellow colour that appears when conc.nitric acid is leftstanding in an ordinary glass bottle.

(ii) Give the name and formula of the brown - ring formed in the test for nitrates.(iii) Nitric acid is used in etching glass and metalware. Explain why?

Question 7.(a) Given P -11, Q-13, R-15, S-17 are four atoms of different elements.(i) Which of the four atoms are metals.(ii) Which of the metals mentioned in (i) would be most metallic in nature.(iii) Arrange the above elements in decreasing order of the electronegativity.(iv) Name the inert gas of the period.(v) Write the formula of the ion formed by R-15.

(b) State whether the underlined element has undergone oxidation or reductionin the equations given below.

(i) Cl2 + H2S 2HCl + S(ii) Zn + CuSO4 ZnSO4 + Cu(iii) 2KI + H2O2 I2 + 2KOH

(c) Show the formation of ammonium ion.

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