According to the Bohr atomic model, the second energy level in an atom can hold how many electrons?

A) 6

B) 2

C) 18

D) 8

E) 9

 When the following equation is correctly balanced, what is the coefficient for oxygen? S8 (g) + O2 (g) SO3 (g)

A) 4

B) 8

C) 12

D) 6

E) 3

In a gas, the distance between the particles is

A) fixed relative to the size of the molecules.

B) very close relative to the size of the molecules.

C) very large relative to the size of the molecules.

D) close relative to the size of the molecules.

E) small relative to the size of the molecules. 

Calculate the molar mass of magnesium chloride, MgCl2 .

A) 70.8 g

B) 125.9 g

C) 24.3 g

D) 95.1 g

E) 59.7 g

What unit of temperature is used in gas law calculations?

A) Kelvin

B) degrees Celsius

C) degrees Fahrenheit

D) either degrees Celsius or Kelvin

E) either degrees Celsius or degrees Fahrenheit

A) Kelvin

How many grams of NO (30.0 g/mol) are required to produce 145 g of N2 (28.0 g/mol) in the following reaction? 4NH3(g) + 6NO(g) 5N2(g) + 6H2O(l)

A) 125 g

B) 155 g

C) 129 g

D) 145 g

E) 186 g

An increase in the temperature of a solution usually

A) increases the solubility of a solid solute in the solution.

B) decreases the solubility of a liquid solute in the solution.

C) decreases the solubility of a solid solute in the solution.

D) increases the boiling point.

E) increases the solubility of a gas in the solution.

The atmospheric pressure in Denver, CO is 633 mmHg. What is this pressure in atm?

A) 633 atm

B) 127 atm

C) 1.20 atm

D) 0.833 atm

E) 1.00 atm 

Which one of the following compounds will NOT be soluble in water?

A) MgCl2

B) K2S

C) BaSO4

D) NaNO3

E) LiOH

In this reaction, what is the substance oxidized? 2Al(s) + 6 HCl(aq)  2AlCl3(aq) + 3H2(g)

A) hydrogen

B) aluminum

C) oxygen

D) chlorine

E) aluminum chloride

The unit of 1 atmosphere used to describe the pressure of a gas is equal to

A) 100 mmHg.

B) 600 mmHg.

C) 1 mmHg .

D) 760 mmHg.

E) 200 mmHg

In the kinetic molecular theory of gas behavior, the assumption is made that gas molecules

A) are attracted to each other by strong forces.

B) move rapidly in random directions.

C) occasionally come to rest.

D) are close together in their container.

E) move with a kinetic energy equal to their centigrade temperature.

 How many atoms of neon (Ne) are present in 1.30 moles of neon?

A) 7.83 × 1024 atoms

B) 4.63 × 1023 atoms

C) 3.15 × 1023 atoms

D) 7.83 × 1023 atoms

E) 6.02 × 1023 atoms

When solutions of KCl and Pb(NO3)2 are mixed, a precipitate forms. Which of the following is the balanced equation for the double replacement reaction that occurs?

A) K+(aq) + NO3-(aq) KNO3(aq)

B) 2KCl (aq) + Pb(NO3)2(aq)  2KNO3(aq) + PbCl2 (s)

C) KNO3(aq) + PbCl2(s)  KCl(aq) + Pb(NO3) 2(aq)

D) KCl(aq) + Pb(NO3)2(aq)  KNO3(aq) + PbCl(s)

E) KCl(aq) + Pb(NO3) 2(aq)  KNO3(aq) + PbCl2(s)

According to Avogadro's law

A) the volume of a gas depends only on the number of moles in the sample.

B) the volume of a gas is inversely related to the number of moles at standard temperature and pressure.

C) the volume of a gas is directly related to the number of moles at constant temperature and pressure.

D) the volume of a gas is inversely related to the number of moles at constant temperature and pressure.

E) the volume of a gas depends only on the temperature and pressure.

Vapor pressure can be described as

A) the temperature at which the vapor pressure of a liquid equals atmospheric pressure.

B) the pressure exerted on the Earth by the particles in the air.

C) the pressure exerted by a gas above the surface of its liquid.

D) the temperature at which bubbles of vapor appear in a liquid.

E) the pressure within the lungs during inhalation. 

The number of electron levels in a aluminum (Al) atom is

A) 1.

B) 2.

C) 3.

D) 4.

E) 5. 

In water, a substance that partially ionizes in solution is called a

 A) strong electrolyte.

B) semiconductor.

C) nonelectrolyte.

D) nonconductor.

E) weak electrolyte. 

How many hydrogen atoms are present in 4.17 moles of H2O (18.0 g/mol)?

A) 4.17 atoms

B) 2.51 × 1024 atoms

C) 5.02 × 1024 atoms

D) 7.53 × 1024 atoms

E) 75.0 atoms

The mathematical expression of the ideal gas law is

A) PT = P1 + P2 + P3.

B) P1 T1 = P2 T2 .

C) P1 V1 = P2 V2 .

D) P1V1 = P2V2.

E) PV = nRT.

Complete the following statement: In Charles's Law, the volume of a gas ________ when the ________ decreases.

A) increases; pressure

B) decreases; pressure

C) decreases; temperature

D) increases; temperature

E) increases; quantity of gas

Sunflower oil does not dissolve in water because

A) water is saturated.

B) Sunflower oil is nonpolar and water is polar.

C) water has a different density than sunflower oil.

D) Sunflower oil is hydrated.

E) Sunflower oil is polar and water is nonpolar. 

What process does the following equation represent? 2Fe2+ + Sn4+  2Fe3+ + Sn2+

A) electronization

B) transformation

C) oxidation-reduction

D) double replacement

E) equalization 

Which set of numbers will correctly balance the given equation? ___Mg(NO3) 2 (aq) + ___Na2Cr2O7 (aq)  ___MgCr2O7 (s) + ___NaNO3 (aq)

A) 1, 4, 1, 2

B) 1, 1, 1, 2

C) 1, 2, 2, 2

D) 3, 2, 3, 2

E) 2, 1, 1, 4

A gas at 5.00 atm pressure was stored in a tank (constant volume) during the winter at 5.0 °C. During the summer, the temperature in the storage area reached 40.0 °C. What was the pressure in the gas tank then?

A) 0.625 atm

B) 4.44 atm

C) 40.0 atm

D) 5.63 atm

E) 69.5 atm

 Zn(s) + 2HCl(aq)  H2(g) + ZnCl2(aq) When 25.0 g of Zn (65.3 g/mol) reacts, how many L of H2 (2.00 g/mol) gas are formed at STP?

A) 0.382 L

B) 8.58 L

C) 0.0171 L

D) 22.4 L

E) 4.28 L

How many equivalents are present in 5.0 moles of Al3+?

A) 5.0 Eq

B) 1.3 Eq
C) 15 Eq

D) 3.0 Eq

E) 0.67 Eq

What type of reaction is represented by the following equation? 2HgO (s)  2Hg (l) + O2 (g)

A) product formation

B) decomposition

C) combination

D) double replacement

E) single replacement

For the chemical reaction: 2Mg + O2  2MgO, calculate the number of moles of MgO produced when 0.20 mole of O2 reacts completely is

A) 0.80 mole.

B) 0.10 mole.

C) 0.40 mole.

D) 0.60 mole.

E) 0.20 mole. 

The reaction shown is A + 2B  3C + 123.4 kJ

A) endothermic.

B) posithermic.

C) exothermic.

D) thermoneutral.

E) enterothermic. 

For the given reaction given below, we start with 5.50 moles of aluminum and 10.0 moles of chlorine. How many moles of chlorine will be left over at the end of the reaction? 2Al (s) + 3Cl2 (l)  2AlCl3 (s)

A) 1.75

B) 8.25

C) 7.25

D) 1.25

E) No chlorine will be left over.

What is the formula of the nitrate ion?

A) NO3 -

B) N3-

C) NO2 -

D) NO3 2-

E) NO3 3

If the reaction shown below is exothermic, the energy level of the reactants is H2 + O2  2H2 O

A) lower than that of the products.

B) higher than that of the products.

C) the same as that of the products.

D) higher than the activation energy of the reaction.

E) possibly lower, possibly higher than that of the products

At STP, what is the volume of 4.50 moles of nitrogen gas?

A) 3420 L

B) 60.7 L

C) 167 L

D) 1230 L

E) 101 L 

At constant temperature, a sample of helium at 760. torr in a closed container was compressed from 5.00 L to 3.00 L, with no change in moles or temperature. What was the new pressure exerted by the helium on its container?

A) 1270 torr

B) 800. torr

C) 2280 torr

D) 15.0 torr

E) 3800 torr

Avogadro's number is the number of

A) moles in 6.02 × 1023 amu of an element.

B) particles in 1 mole of a substance.

C) grams in 1 mole of a substance.

D) amu in 1 mole of a substance.

E) moles in 6.02 × 1023 grams of an element

In a solution, the solvent

A) can be a liquid or gas.

B) is never a solid.

C) is a liquid.

D) is the substance present in the smallest concentration.

E) can be a solid, liquid, or gas.

A cyclopropane (C3H6)-oxygen (O2 ) mixture is used as an anesthetic. If the partial pressure of cyclopropane in the mixture is 330 mmHg and the partial pressure of the oxygen is 1.0 atm, what is the total pressure of the mixture in torr?

A) 1.4 torr

B) 330 torr

C) 430 torr

D) 760 torr

E) 1100 torr

What is required for a nuclear transmutation to occur?

A) spontaneous nuclear decay

B) gamma emission

C) a particle to collide with a nucleus

D) very high temperature

E) a corrosive environment

What type of reaction is represented by the following equation? AB + C  AC + B

A) double replacement

B) single replacement

C) decomposition

D) combustion

E) combination 

Classify the reaction represented by the following equation. 2C2H6 + 7O2  4CO2 + 6H2O

A) single replacement

B) combination

C) decomposition

D) double replacement

E) combustion 

When some of the sugar added to iced tea remains undissolved at the bottom of the glass, the solution is

A) nonpolar.

B) saturated.

C) dilute.

D) unsaturated.

E) polar

 What is the correct form of the conversion factor (mole ratio) needed to convert the number of moles of H2O to the number of moles of NH3 produced? Mg3N2 (s) + 6H2O(l)  3Mg (OH)2 (s) + 2NH3 (g)

A) 18 g of H2O 17 g of NH3

B) 6 moles of H2O 2 moles of NH3

C) 18 g of H2O 1 mole of H2O

D) 1 mole of Mg3N2 6 moles of H2O

E) 1 moles of NH3 3 moles of H2O

For the exothermic reaction: O2 (g) + 2H2(g)  2 H2O (l) + 137 kcal, how many kcal are gained to form 4.00 moles H2O(l)?

A) 548 kcal

B) 190 kcal

C) 274 kcal

D) 68.5 kcal

E) 137 kcal

A student prepares ethyl bromide (C2H5Br) by heating ethyl alcohol (C2H5OH)with aqueous HBr. The students starts with 60.0 g of ethyl alcohol (46.0 g/mol) and excess HBr (80.9 g/mol), and obtains 100.0 g of ethyl bromide (108.9 g/mol). What is the percent yield of ethyl bromide? C2H5OH (l) + HBr (aq)  C2H5Br (l) + H2O (l)

A) 1.42%

B) 70.4%

C) 42.0%

D) 29.6%

E) 142%

A solution is prepared by dissolving 2 g of KCl in 100 g of H2O. In this solution, KCl is the

A) solid.

B) solute.

C) ionic compound.

D) solvent.

E) solution.

Classify the reaction represented by the following equation. Hg2(ClO3) 2 + MgBr2 Hg2Br2 + Mg(ClO3) 2

A) combustion

B) combination

C) decomposition

D) double replacement

E) single replacement

What is the mass of a sample of O2 gas (32.0 g/mol), which has a pressure of 740. mmHg, at a temperature of 25 °C, in a volume of 0.250 L?

A) 201 g

B) 320. g

C) 3.82 g

D) 0.318 g

E) 292 g

The How many moles of hydrogen are in 1.20 moles of bromo-benzene (C6H5 Br)?

A) 14.4

B) 6.00

C) 6.00

D) 5.00

E) 1.20