second periodical exam chemistry 2011 - 2012

7/30/2019 Second Periodical Exam Chemistry 2011 - 2012

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GENERAL SANTOS HOPE CHRISTIAN SCHOOLBlock 8, City Heights, General Santos City

SECOND PERIODICAL EXAMINATION

ADVANCED CHEMISTRY IFOURTH YEAR A and BSY: 2011 - 2012

NAME : _______________________ SCORETeacher: ROGELIO B. PONTEJO Date: ___________.

I. Multiple Choice: Choose the correct answer. Write the answer in the spaceprovided before each item.

___B_____ 1. Ozone is a(n) __________ of oxygen.

A. isomerB. allotropeC. isotopeD. resonance structure

____B____2. CFC stands for __________.

A. chlorinated freon compound

B. chlorofluorocarbon

C. carbonated fluorine compound

D. caustic fluorine carbohydrate

____A___3. Natural, unpolluted rainwater is typically acidic. What is the source of this natural

acidity __________?

A. 2CO

B. 2SO

C.2

NO

D. HCl

___B____4. What compound in limestone and marble is attacked by acid rain __________?

A. hydroxyapatite

B. calcium carbonate

C. gypsum

D. graphite

____A___5. 2CO from hydrocarbon combustion creates a major environmental problem that isdescribed as __________.

A. the greenhouse effectB. photochemical smog

C. acid rain

D. stratospheric ozone depletion


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___C__13. A single individual typically uses the greatest quantity of water for __________.

A. flushing toilets

B. cooking

C. cleaning (bathing, laundering, and house cleaning)

D. watering lawns

___A__14. Water containing high concentrations of __________ cations is called hard water.

A) 2Ca or2Mg

B) 2Mg

C) Na

D) K ___D___15. A strong acid

A. ionizes completely in solution.

B. produces hydronium ions in solution.

C. reacts with metals that are more active than hydrogen.

D.All of the above

___D_____16. An Arrhenius acid is a chemical compound that

A. does not conduct electricity.

B. increases the concentration of H_ions in solution.

C. reacts with water to remove H_ions.

D. dissociates to release OH_ ions in solution.

_________17. In the following reaction, which substance acts as a Brnsted-Lowry base?

HCl + NH3 NH4 + Cl_A. HCl

B. NH3

C. NH4 -

D. Cl_

________18.Which of the following is a polyprotic acid?

a. HClb. H2SO4

c. HNO3

d.HF

_______19.Which stage of ionization of H3PO4 produces the most ions in solution?

________20. Which of the following substances can act as an Arrhenius base, a Brnsted-Lowrybase, and a Lewis base?

A.B.C.D.

A.B.C.D.


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_______ 21. Which of the following will be present in an aqueous solution of H2SO4?

_______22. Which of the following characteristics describes a base?

A. reacts with oils in the skin and converts them to acids

B. forms alkaline solutions

C. is a nonelectrolyte

D. None of the above

________23. All Brnsted-Lowry acids

A. are aqueous solutions.

B. can act as Arrhenius acids.

C. donate protons.

D. All of the above

_______24. A Lewis acid

A. is an anion.

B. donates an electron pair to form a covalent bond.

C. can be a substance that does not contain a hydrogen atom.

D. All of the above

________25. A conjugate acid is an acid that forms when

A. the acid gains a proton.

B. a base loses a proton.

C. a base gains a proton.

D. an atom accepts an electron pair.

_______26. Ions that are present before and after a neutralization reaction are

A. nonelectrolytes.

B. metal ions.

C. neutral ions.

D. spectator ions.

_______27. A conjugate base is the species that

A. remains after a base has given up a proton.

B. is formed by the addition of a proton.

C. is formed by the addition of a proton to a base.

D. remains after an acid has given up a proton.

_______28. Water is amphoteric. If it reacts with a compound that is a stronger acid than itself,

water acts as a

A. weak base.

B. strong base.

C. weak acid.

D. hydroxide ion.

A.B.C.D.


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_______29. A solution that has a pH of 13 is a

A. strong acid.

B. strong base.

C. weak acid.

D. weak base.

______30. What is the [OH_] in a sample of lime juice with a pH of 2.0?

A. 1.0_10_2 MB. 1.0_10_7 MC. 1.0_10_10 MD. 1.0_10_12 M

________31. What is the reason for the relatively low density of ice?

A. empty spaces between molecules

B. the high number of hydrogen bondsC. the small size of hydrogen and oxygen atoms

D. the low molar mass of water

_______32. All of the following are homogeneous mixtures except

A. tomato soup.

B. a sugar-water solution.

C. gasoline.

D. a salt-water solution.

______ 33. A mixture that appears to be uniform while being stirred but which separates into

different phases when agitation ceases is a

A. solvent.

B. colloid.

C. suspension.

D. solute.

______ 34. What type of solute-solvent combination is carbon dioxide in air?

A. gas-liquid

B. liquid-gas

C.liquid-liquidD. gas-gas

_______35. A substance that is notsoluble in a polar solvent is most likely

A. nonpolar.

B. ionic.

C. polar.

D. hydrogen bonded.

______ 36. Sugar is soluble in water because sugar molecules are

A. massive.B. large.

C. nonpolar.

D. polar.


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______37. Which of the following actions does not, in general, increase the solubility of a solid in a

liquid?

A. increasing the temperature of the solvent

B. increasing the surface area of the solute

C. increasing the pressure of the solution

D. shaking or stirring the solution

______38. If the amount of dissolved solute in a solution at a given temperature is greater than the

amount that can permanently remain in solution at that temperature, the solution is said

to be

A. saturated. C. supersaturated

B. unsaturated. D. diluted

______ 39. All of the KBr that will dissolve in a solution has dissolved, and several undissolved

crystals remain on the bottom of the beaker. The solution is

A. saturated.

B. supersaturated.

C. unsaturated.

D. at the incorrect pressure to dissolve the solid.

______ 40. How can you best increase the solubility of a gas in a liquid?

A. Increase both the temperature and the pressure.

B. Decrease both the temperature and the pressure.

C. Increase the temperature and decrease the pressure.

D. Decrease the temperature and increase the pressure.

______ 41. The enthalpy of solution for solid AgNO3 is positive. What does this tell you about the

formation of a AgNO3 solution?

A. AgNO3 will not form a solution.

B. Energy is released during the solution process.

C. AgNO3 will dissolve only under high pressure.

D. Energy is absorbed during the solution process.

______42. When preparing 500. mL of a 1.35 M aqueous solution of NaCl, what should you do

after adding the correct amount of solute to a large beaker?

A. Add 500. mL of water, and stir until solute dissolves.

B. Add 500. mL of water, dissolve solute, and add to a volumetric flask.

C. Add 400 mL of water, dissolve solute, add to a volumetric flask, add water to 500.

mL mark, and mix thoroughly.

D. Add 400. mL of water, dissolve solute, add to a volumetric flask, add 100. mL of

water, mix thoroughly, and transfer to another container.

______43. When preparing a 2.50 m aqueous solution of KOH, you correctly calculate that you need

140.3 g of KOH and 1.000 Kg (or 1.000 L) of water. What should you do after adding

140.3 g of KOH to a large beaker?

A. Add 1000. mL of water, and stir until solute dissolves.B. Add 900. mL of water, dissolve solute, add to a volumetric flask, and then add

water to the 1000. mL mark.

C. Add 900. mL of water, dissolve solute, add to a volumetric flask, add water to

1000. mL mark and mix thoroughly.

D. Add 900 mL of water, dissolve solute, add to a volumetric flask, add water to

1000. mL mark, mix thoroughly, and transfer to another container.


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______ 44. Which of the following is notused in preparing a 0.300 m aqueous solution of NaBr

(molar mass_102.89 g/mol) with 1.00 Kg of solvent?

A. 0.300 mol water

B. 0.300 mol NaBr

C. graduated cylinder

D. 0.300 mol_molar mass of NaBr

______ 45. Which of the following statements about concentration is true?

A. A concentrated solution may be saturated.

B. A saturated solution may be dilute.

C. A dilute solution may be unsaturated.

D. All of the above

_______46. How many grams of CaCl2 (molar mass_110.98 g/mol) are needed to prepare 1.00 Lof a 1.00 M solution?

A. 1.00 g

B. 40.08 g

C. 75.53 g

D. 110.98 g

______ 47. You know the mass of solute and the volume of solution. What is the first step in finding

the molarity of the solution?

A. Divide the mass by molar mass to determine number of moles.

B. Divide the mass by the volume of solution.

C. Divide the volume of solution by its mass.

D. Divide the number of moles by the volume of solution.

______48. What does the 254 in fermium-254 represent?

A. mass number

B. atomic number

C. number of neutrons

D. number of protons

______49. Which of the following best identifies the neutron-proton ratio referred to as the band of

stability?

A. for low atomic numbers, 1 : 1

B. for high atomic numbers, 1.5 : 1

C. for most elements, 1 : 1.25

D. Both (a) and (b)

______50. Which combination of protons and neutrons results in the most stable nuclei?

A. even number of protons; odd number of neutrons

B. even number of protons; even number of neutrons

C. odd number of protons; even number of neutrons

D. odd number of protons; odd number of neutrons

______51.

A. alpha decay.

B. beta decay.

C. electron capture.

D. fusion.


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_____52. What percentage of the original amount of carbon-14 remains in a 20 g sample after two

half-lives?

A. 50% B. 25% C. 20% D. 0%

______53. A 0.15 M solution of HCl reacts with an excess of calcium carbonate, CaCO3. A volume

of 25.0 mL of HCl is used. To determine the number of moles of CaCl2 produced, you

need to know

A. the amount of the other product produced.

B. the molar mass of HCl.

C. the molar mass of CaCl2.

D. the balanced chemical equation for the reaction.

_ 54. Which of the following statements concerning a saturated solution isincorrect?

A. Undissolved solute must be present.B. Undissolved solute may or may not be present.C. Undissolved solute, if present, is continually dissolving.D. Undissolved solute, if present, is in equilibrium with dissolved solute.

_ 55. Which of the following statements concerning factors that affect solutesolubility is incorrect?

A. Most solid solutes become more soluble in water with increasingtemperature.

B. Most solid solutes become less soluble in water with decreasing

pressure.C. Gaseous solutes become less soluble in water with increasing

temperature.D. Gaseous solutes become more soluble in water with increasing

pressure.

_ 56. The solubility rule like dissolves like is not adequate for predictingsolubilities when the solute is a(n)

A. nonpolar gas. C. nonpolar liquid.B. ionic compound. D. polar gas

_ 57. Calculate the concentration in % (m/m) of a solution containing 20.0 g ofNaCl dissolved in 250.0 g of H2O.

A. 6.76% (m/m) C. 8.00% (m/m)B. 7.41% (m/m) D. 8.25% (m/m)

_ 58. Calculate the grams of NaOH present in 5.0 mL of a 1.0% (m/v) NaOHsolution.

A. 0.050 g C. 0.50 g

B. 0.10 g D. 1.0 g

_ _59. The defining expression for the molarity concentration unit is

A. moles of solute/liters of solution.B. moles of solute/liters of solvent.C. grams of solute/liters of solution.D. grams of solute/liters of solvent.


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_ 60. A solution is made by dissolving 0.40 mole of NaCl in enough water to givea final volume of 250.0 mL. What is the molarity of the solution?

A. 0.10 M C. 1.6 MB. 0.80 M D. 2.5 M

_ 61. What is the molarity of a solution containing 17.0 grams of NH3 in 1.20 litersof solution?

A. 0.0833 M C. 1.42 MB. 0.833 M D. 14.2 M

_ 62. A 0.200 M solution of NaOH, which contains 0.250 mole of solute, wouldhave a volume, in milliliters, of

A. 20.0 mL. C. 725 mL

B. 50.0 mL. D. 1250 Ml.

_ 63. A colloidal dispersion differs from a true solution in that colloidal particles

A. tend to settle at an appreciable rate.B. are large enough to scatter light.C. are large enough to be seen with the naked eye.D. are large enough to be seen with a microscope.

_ 64. Compared to pure water, a 1 M sugar-water solution will have a

A. lower vapor pressure, lower boiling point and lower freezing point.B. higher vapor pressure, higher boiling point and higher freezing point.C. lower vapor pressure, higher boiling point and lower freezing point.D. lower vapor pressure, lower boiling point and higher freezing point.

_______65. Given the balanced equation representing a nuclear reaction:

. Which particle is represented byX?

A. C.

B. D.

_______66. What is the oxidation half-reaction for the following redox reaction?

______67. The charge of an oxygen atom in Na2O2 is

A. 2 B. 1 C. 0 D. -1

A.B.C.

D.


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_______68. What is the reduction half-reaction for the following redox reaction?

_______69.

________70. The term oxidation arose early in the history of chemistry, when scientists observedelements combining with oxygen in combustion reactions.

II. BALANCING REDOX REACTION IN ACIDIC MEDIUM: (5 points)

Cr2O72(aq) + HNO2(aq) Cr

3+(aq) + NO3(aq) (acidic)

A.

B.C.D.

A.B.C.D.

A.B.C.D.

second periodical exam chemistry 2011 - 2012

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