Chemst Prep-test3

8/7/2019 Chemst Prep-test3

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Chemst Prep-test 75 questions (may use periodic table & formula sheet at end of document, no calculators!)

1. A weather balloon with a 2-meter diameter at

ambient temperature holds 525 grams of helium.

What type of electronic probe could be used to

determine the pressure inside the balloon?

A barometric B thermometric

C calorimetric D spectrophotometric

2. Which would bemost appropriate for collecting

data during a neutralization reaction?

A a pH probe B a statistics program

C a thermometer D a graphing program

3. A scientist saw a gas pressure change of one mole

of a gas in a sealed chamber with a fixed volume. To

identify the source of the changes, the scientist

should check for variations in the

A air pressure outside the chamber.

B molecular formula of the gas.

C temperature of the chamber.D isotopes of the gas.

4Electrical fires cannot be safely put out bydousing them with water. However, fire

extinguishers that spray solid carbon dioxide on the

fire work very effectively. This method works

because carbon dioxide

A displaces the oxygen.

B renders the fires fuel non-flammable.

C forms water vapor

D blows the fire out with strong wind currents.

5. In order to advance to the level of a theory, a

hypothesis should be

A accepted by most people.

B a fully functional experiment.

C aligned with past theories.

D repeatedly confirmed by experimentation.

6 Matter is made of atoms that have positive centers

of neutrons and protons surrounded by a cloud of

negatively charged electrons. This statement is

A a theory. B a hypothesis.

C an inference. D an observation.

7 When a metal is heated in a flame, the flame has a

distinctive color. This information was eventually

extended to the study of stars because

A Star spectra shows the elements present.

B a red shift means stars are moving away.

C star color shows distance.

D You can find their size.

8. See figure below, then answer the question.

8. Which ordered pairs of elements shows an

increase in atomic number but a decrease in

average atomic mass? (Hint: Use your periodic

table)

A Ag to Pd B Co to Ni C Ge to Sn D Cr to Mo

9Why is cobalt (Co) placed before nickel (Ni) onthe periodic table of the elements even though it has

a higher average atomic mass than nickel?

A Ni has 1 more proton B Co was discovered 1st.

C Ni has fewer electrons D Co has lower density.

10. Generally, how do atomic masses increase

throughout the periodic table of the elements?A left to right & top to bottom.

B left to right & bottom to top.

C right to left & top to bottom.

D right to left & bottom to top.

11. See figure, then answer the question.

Iodine has chemical properties most like

A. manganese (Mn). B. tellurium (Te).

C. chlorine (Cl). D. xenon (Xe).


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12.

The chart shows the relationship between the first

ionization energy & the increase in atomic number.

The letter on the chart for the alkali elements is

A W. B X. C Y. D Z.

13 Which has six valence electrons?

A magnesium (Mg) B silicon (Si)

C sulfur (S) D argon (Ar)

14 An atoms nucleus density is best described asA large volume/small mass B small volume & mass

C large volume & mass D small volume/large mass


Above indicates the nucleus of the gold atom

A has less than half the mass. B is small & dense.

C has small (+) & (-) particles. D is large & has

most of the space.

16Why are enormous amounts of energy needed toseparate a nucleus into protons & neutrons even

though the protons repel each other? (Hint: look

up nuclear binding energy)

A Proton-repelling force is less than neutron-

attracting force.

B Electrostatic forces among other atoms lower

proton-repelling force.

C Neutron & electron interactions neutralize

proton-repelling force.

D Forces holding nuclei together are stronger

than proton-repelling force.

17. Which equation correctly represents the alpha

decay of polonium-21 (answers continue nextcolumn)

A. B.

C. D.

18.A 2-cm-thick piece of cardboard placed over a

radiation source would bemost effective in

protecting against which type of radiation?

A alpha B beta C gamma D x-ray

19 Which is a monatomic gas at STP?

A chlorine B fluorine C helium D nitrogen

20. Cations & anions form what kind of bond?

A ionic B hydrogen C metallic D covalent

21 Some molecules in body are NH2CH2COOH

(glycine), C6H12O6 (glucose), and CH3(CH2)16COOH

(stearic acid). The bonds they form are

A nuclear. B metallic. C ionic. D covalent.


What bond do these molecules have in common?

A. Covalent B. Ionic C. Metallic D. Polar

23. S crystals like KCl, hold together well because

the cations are strongly attracted to

A neighboring cations. B neighboring protons.C free electrons in the crystals. D neighboring anions.

24 Under same pressure & temperature, a liquid

differs from a gas because the liquid molecules have

A no regular arrangement .

B constant motion

C stronger forces of attraction between them.

D the shape of the container they are in.

25. See figure below, then answer the question

Which has the same Lewis dot structure as silicon?

(Hint: Use the attached periodic table)

A germanium (Ge) B aluminum (Al)

C arsenic (As) D gallium (Ga)


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26. Which substance is made up of many monomers

joined together in long chains?

A salt B protein C ethanol D propane

27 For the polymer, polyvinyl chloride (PVC)

~CH2CH(Cl)CH2CH(Cl)CH2CH(Cl)~ the repeating

subunit is

A CH(Cl). B CH(Cl)CHCH2

C CH2CH D CH2CH(Cl)

28 Which element is capable of forming stable,

extended chains of atoms through single, double, or

triple bonds with itself?

A carbon B oxygen C nitrogen D hydrogen

29 Proteins are large macromolecules with 1000s of

subunits. Their structure depends on a sequence of

A lipids. B monosaccharides.

C amino acids. D nucleosides.

30. It takes several minutes for someone at the otherend of a room to smell an open bottle of vinegar.

Since gas molecules at room temperature move very

fast, what causes this delay?

A Increased airspace of vinegar molecules

B the chemical reaction with nerves, which is

slower than other sensory processes

C attractive forces between air & vinegar molecules

D random collisions between air & vinegar

molecules

31 Methane (CH4) gas diffuses through air because

the molecules areA moving randomly. B dissolving quickly.

C traveling slowly. D expanding steadily.

32 The volume of 400 mL of chlorine gas at 400 mm

Hg is decreased to 200 mL at constant temperature.

What is the new gas pressure in mm Hg?

A 400 B 300 C 800 mm Hg D 650

33. When may a gas volume decrease when heated?

A Held constant at STP. B Stays at same temperature.

C Apply pressure. D Lower the pressure.

34 Standard temperature and pressure (STP) are

defined as

A 0 C & 1.0 atm. B 0 C & 273 mm Hg.

C 0 K & 1.0 atm. D 0 K & 760 mm Hg.

35 Under which set of conditions will a 0.50 mole

sample of helium occupy a volume of 11.2 liters?

A 298 K and 0.90 atm B 273 K and 1.10 atm

C 373 K and 0.50 atm D 273 K and 1.00 atm

36 What is 423 Kelvin in degrees Celsius?

A -223 C B -23 C C 150 C D 696 C

37. Theoretically, when an ideal gas in a closed

container cools, the pressure will drop steadily until

the pressure inside is essentially that of a vacuum.

At what temperature should this occur?

A 0C B460 C C273 K D 0 K


Which of the substances in the table can act as

either the solute or the solvent when mixed with 100

grams of water at 20 C?

A NH3 B C6H5COOH C MgCl2 D CH3CH2OH

39.If the attractive forces among solid particles are

less than the attractive forces between the solid and

a liquid, the solid will probably

A form a new precipitate as its crystal lattice is broken

& re-formed.B be unaffected because attractive forces within the

crystal lattice are too strong for dissolution to occur.

C begin the process of melting to form a liquid.

D dissolve as particles are pulled away from the crystal

lattice by the liquid molecules.

40. Water is a polar solvent, while hexane is a

nonpolar solvent.

Which is a nonpolar solute in a polar solvent?

A NH4Cl in water B C10H8in water

C C2H5OH in hexane D CO(NH2)2 in hexane

41 If the solubility of NaCl at 25 C is 36.2 g/100 gH2O, what mass of it can dissolve in 50.0 g of H2O?

A 18.1 g B 36.2 g C 72.4 g D 86.2 g

42 How many moles of NHO3 are needed to prepare

5.0 liters of a 2.0 M solution of HNO3?

A 2.5 B 5 C 10 D 20


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43. The Dead Sea contains 332 grams of salt per

1000 grams of water. What is the concentration in

parts per million (ppm)?

A 0.332 ppm B 332 ppm

C 33,200 ppm D 332,000 ppm

44 The random molecular motion of a substance is

greatest when the substance is

A condensed. B a liquid. C frozen. D a gas.

45 Which of these is an example of an exothermic

chemical process?

A water evaporation B ice melting

C glucose photosynthesis D gasoline combustion

46. Liquid nitrogen boils at 77 kelvin. Ice forms at

the opening of a container of liquid nitrogen. The

best explanation is

A water at zero degrees Celsius is colder than liquid

nitrogen and freezes.

B the nitrogen boils and then cools to form a solid at

the opening of the container.

C water trapped in the nitrogen escapes and freezes.

D the water vapor in the air over the opening of the

liquid nitrogen freezes out.

47 The specific heat of copper is about 0.4 J/g C.

What heat will change the temperature of 30 grams

of copper from 20.0 C to 60.0 C?

A 1000 J B 720 J C 480 J D 240 J

48 When equal volumes of 1Mhydrochloric acid(HCl) & 1Msodium hydroxide base (NaOH) are

mixed the solution will be

A strongly acidic. B weakly acidic.C nearly neutral. D weakly basic.


This picture shows a light bulb connected to a

battery with the circuit interrupted by a solution.

When dissolved in the water to form a 1.0 molar

solution, all of the following substances will

complete a circuit allowing the bulb to light except

A hydrochloric acid. B sodium nitrate.

C sucrose. D ammonium sulfate.

50 Which of the following is an observable property

of many acids?

A Become slippery when reacting with water.

B React with metals to release hydrogen gas.

C Produce salts when mixed with other acids.

D Become more acidic when mixed with a base.

51 Copper (II) nitrate and sodium hydroxide

solutions react as follows:Cu(NO3)2(aq) + 2NaOH(aq) Cu(OH)2(s) +2NaNO3(aq) If nitric acid is added the amount of

solid precipitate decreases. Thebest explanation is

that the acid

A dilutes the solution making the precipitate dissolve.

B reacts with the copper (II) nitrate, pulling the

equilibrium to the left.

C will dissolve most solids, including sodium nitrate.

D will react with the copper (II) hydroxide to form

water and soluble copper (II) nitrate.

52Potassium hydroxide (KOH) is a strong basebecause it

A easily releases hydroxide ions.

B does not dissolve in water.

C reacts to form salt crystals in water.

D does not conduct an electric current.

53 Of four different laboratory solutions, the

solution with thehighest acidity has a pH of

A 11 B 7. C 5 D 3.

54.Which of the following changes will cause an

increase in the rate of the above reaction?

A increase [Br2] B decrease [C6H6]

C increase [HBr] D decrease the temperature

55. 2CO2 + O2 2CO2 If this reaction is inside asealed reaction chamber, then which of these will

decrease in the reaction rate?

A raise the temperatureB increase the volume in the chamber

C remove CO2as it is formed

D add more CO to the chamber

56 A catalyst speeds up the reaction rate by

A increasing the equilibrium constant in favor of

products.

B lowering the activation energy

C raising the temperature.

D increasing the pressure of reactants, thus favoring

products.


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57. Which shows the effect of using a catalyst?

58. H2O2, hydrogen peroxide, naturally breaks

down into H2Oand O2over time. MnO2,manganese

dioxide, can be used to lower the energy of

activation needed for this reaction to take place

and, thus, increase the rate of reaction. What type

of substance is MnO2?

A catalyst B enhancer C inhibitor D reactant

59 When a reaction is at equilibrium and more

reactant is added, which of the following changes is

the immediate result?A Reverse rate stays same. B Forward rate increases.

C Reverse rate decreases. D Forward rate stays same.

60 Which gas reaction below would the forward

reaction be favored by an increase in pressure?

A A + B AB B A + B C + D

C 2A + B C + 2D D AC A + C

61.

Which action will drive this reaction to the right?

A heating B adding water

C decreasing the [O2] D increasing pressure

62. occurs

in a closed flask. What will shift it to the left?

A pumping in CO gas B raising total pressureC increasing [NO] D venting some CO2 gas

63

What change will shift the reaction to the right to

form more products?

A decreasing pressure B increasing [HCl]

C increasing NH3pressure D decreasing temperature

64. In a sealed bottle that is half full of water,

equilibrium will be attained when water molecules

A stop evaporating.

B begin condensing.C are equal in number for both liquid & gas phases.

D evaporate & condense at equal rates.

65. C3H8 + O2 CO2 + H2O is thecombustion of propane. When correctly

balanced, the coefficient for water is

A 2. B 4. C 8. D 16.

66 Which is a balanced equation for the combustion

of ethanol (CH3Ch2OH)?

A. CH3CH2OH + 3O2 CO2 + H2O

B. CH3CH2OH + 3O2 2CO2 + 3H2OC. H3CH2OH + O2 2CO2 + 3H2O

D. H3CH2OH + 2O2 3CO2 + 2H2O

67 How many moles of carbon-12 are in exactly 6

grams of carbon-12?

A 0.5mole B 2.0 .moles

C 3.01 1023

moles D 6.02 1023

moles

68. How many atoms are in 97.6 g of platinum (Pt)?

A 5.16 1030

B 3.01 1023

C 1.20 1024

D 1.10 1028

69 Methane (CH4) gas is burned in oxygen as

follows: CH4 + 2O2 CO2 + 2H2O If 1 mole ofmethane reacts with 2 moles of oxygen, then

A 6.02 1023

molecules each of CO2& H2O are made.

B 1.2 1024molecules each of CO2 & H2O are made

C 6.02 1023 molecules CO2 & 1.2 10

24 molecules

H2O are made

D. 1.2 1024 molecules CO2 & 6.02 10

23 molecules

H2O are made


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70 How many moles of CH4

are contained in 96.0

grams of CH?

A 3.00 B 6.00 C 12.0 D 16.0

71. How many atoms are in a chromium sample

with a mass of 13 grams?

A 1.5

10

23

B 3.3

10

23

C 1.9 10

26 D 2.4 10

24

72 How many moles of chlorine gas are contained in

9.02 1023 molecules?A 1.5 moles B 2.0 moles

C 6.02 moles D 9.03 moles

73. Fe2O3 + 3CO 2Fe + 3CO2 How many gramsof Fe2O3 completely react with 84 grams of CO?

A 64 g B 80 g C 160 g D 1400 g

74. Mg3N2 + 6H2O 2NH3 + 3Mg(OH)2If 54.0grams of water are mixed with excess magnesiumnitride, how many grams of ammonia are

produced?

A 1.00 B 17.0 C 51.0 D 153

75 3CuCl2 + 2Al 2AlCl3 + 3Cu How muchcopper is produced if 5.4 grams aluminum (Al)

react with excess copper(II) chloride (CuCl2)?

A 0.65 g B 8.5 g C 13 g D 19 g

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