Chemistry MC: September 2017

A) The pressure will remain the same.
B) The pressure will be half of the original value.
C) The pressure will be twice the original value.
D) It would be impossible to move the piston since gases are not compressible.
E) none of the above

Answer: C

To solve problems using Boyle's Law, which mathematical equation should be used?

A) P1/V1 = P2/V2
B) P1V1 = P2V2
C) V1/P1 = V2/P2
D) P2V1 = P1V2
E) none of the above

Answer: B

Boyle's Law is expressed as

A) V is proportional to 1/P
B) P is proportional to V
C) V is proportional to 1/T
D) V is proportional to T
E) none of the above

Answer: A

What is the equivalent pressure of 968 mm Hg in units of atm?

A) 1.27 atm
B) 0.785 atm
C) 968 atm
D) 1.30 atm
E) none of the above

Answer: A

What is the equivalent pressure of 760 torr in units of mm Hg?

A) 760
B) 1
C) 14.7
D) 29.92
E) none of the above

Answer: A

What is the equivalent pressure of 1520 torr in units of atm?

A) 203,000
B) 380.
C) 2.00
D) 1520
E) none of the above

Answer: C

What is the equivalent pressure of 0.905 atm in units of mm Hg?

A) 688
B) 840
C) 0.905
D) 13.3
E) none of the above

Answer: A

A barometer uses mercury because

A) it is a convenient, safe, lightweight material.
B) the density of mercury is very large which allows the barometer to be short.
C) it is the traditional substance used, water could be as easily used.
D) it is the only liquid metal at room temperature.
E) All of the above are true.

Answer: B

1 torr is equal to

A) 760 mm Hg.
B) 1 mm Hg.
C) 1 Pa.
D) 14.7 psi.
E) all of the above

Answer: B

1 atm is equal to

A) 760 mm Hg.
B) 760 torr.
C) 101,325 Pa.
D) 14.7 psi.
E) all of the above

Answer: E

All of the following statements are consistent with the kinetic molecular theory of gases EXCEPT

A) The size of the gas molecules is negligible compared to the total volume of the gas.
B) The average kinetic energy of the molecules of a gas is proportional to the temperature of the gas in kelvins.
C) The gas molecules collide with each other and with the surfaces around them.
D) Strong attractive forces hold the gas molecules together.
E) none of the above

Answer: D

Which of following statements are consistent with the Kinetic Molecular Theory?

A) Gases are compressible because the volume taken up by the gas is almost entirely open space.
B) Gases assume the shape and volume of their container because they are in constant, straight-line motion.
C) Gases have a low density because there is so much empty space between the particles.
D) Gas particles collide with each other and surfaces without losing any energy.
E) All of the above statements are consistent with the Kinetic Molecular Theory.

Answer: E

Which of the following is NOT part of the Kinetic Molecular Theory?

A) Gas particles do not repel each other.
B) There is a large distance between gas particles as compared to their relative size.
C) The size of the actual gas particles is small compared to the volume of the whole gas.
D) The average energy of the particles is dependent on the molecular mass of the particle.
E) All of the above statements are part of the Kinetic Molecular Theory.

Answer: D

Which of the following statements about pressure is FALSE?

A) Pressure is caused by gas molecules colliding with surfaces.
B) The atmosphere has a pressure as the components of air collide with surfaces.
C) After creating a pressure difference, the atmospheric pressure can push liquid up a straw.
D) A deep well dug in the ground must have the pump located at the bottom of well in order to have the water come to the surface.
E) All of the above statements are true.

Answer: E

Osmotic pressure is

A) the pressure required to stop the flow of solvent from a region of high solute concentration to a region of low solute concentration.
B) the pressure required to stop the rupture of the semipermeable membrane.
C) the pressure required to reverse the flow of solvent through a semipermeable membrane during osmosis.
D) the pressure required to stop the flow of solvent from a region of low solute concentration through a semipermeable membrane into a region of high solute concentration.
E) none of the above

Answer: D

An osmosis cell is constructed of a "U" shaped tube with a semipermeable membrane separating the two arms of the tube. Suppose a concentrated solution is placed in the left arm of the U-tube, and a dilute concentration of the same substance is poured into the other arm to the same height. After a period of time has elapsed, you would expect to find that

A) the level of liquid in the left arm is now higher.
B) the level of the liquid in the right arm is now higher.
C) the levels in both arms stay at the same height.
D) no molecules of any type cross the membrane.
E) none of the above

Answer: A

Solution A has a concentration of 0.10 M sugar and Solution B has a concentration of 0.20 M sugar. If the two solutions are separated by a semipermeable membrane, which of the following occurs during osmosis?

A) Solvent molecules move from B into A.
B) Sugar molecules move from B into A.
C) The molarity of A increases.
D) The molarity of B increases.
E) none of the above

Answer: C

What will happen if a healthy red blood cell is placed into a container of pure water?

A) The cell will totally dissolve in the water.
B) The cell will remain unchanged.
C) The cell will become swollen.
D) The cell will shrink.
E) none of the above

Answer: C

Why is it NOT a good idea to drink seawater when people are lost at sea?

A) The high concentration of salt forces water out of the cells lining your stomach and intestine.
B) The osmotic pressure builds up in the cells of your intestine until they potentially rupture.
C) The semipermeable membrane protecting your stomach is ruptured during osmosis.
D) The seawater has fish urine in it and who wants to drink that?
E) none of the above

Answer: A

What is the change in the freezing point of a solution made by dissolving 14.7 g of C6H12O6 into 150.0 ml of water? The density of water is 1.00 g/mL and Kf=1.86 C/m

A) 0.152°C
B) 1.01°C
C) 18.97°C
D) 1.82°C
E) none of the above

Answer: B

What is the change in the boiling point of a solution made by dissolving 14.7 g of C6H12O6 into 150.0 ml of water? The density of water is 1.00 g.mL and Kb = 0.512 C/m.

A) 0.502°C
B) 5.22°C
C) 0.0418°C
D) 0.279°C
E) none of the above

Answer: D

Which of the following aqueous solutions would be expected to freeze at the lowest temperature?

A) 1 molal KNO3
B) 1 molal NaCl
C) 1 molal CaCl2
D) 1 molal C6H12O6 (fructose)
E) All of these solutions would freeze at the same temperature.

Answer: C

Which of the following statements about colligative properties is FALSE?

A) The boiling point of a solution is increased by the addition of salt.
B) The freezing point of a solution is lowered by the addition of salt.
C) The change in temperature is proportional to the molality.
D) The identity of the solute is not a factor.
E) All of the above statements are true.

Answer: E

What is the molality of a solution made by dissolving 14.7 g of C6H12O6 into 150.0 ml of water? Assume the density of water is 1.00 g/mol.

A) 0.544
B) 0.0816
C) 10.2
D) 0.980
E) none of the above

Answer: A

In comparing a 0.25 molality aqueous NaCl solution to a 0.25 molality aqueous CaCl2 solution

A) the NaCl solution has the higher boiling point and the lower freezing point.
B) the CaCl2 solution has the higher boiling point and the lower freezing point.
C) the NaCl solution has the higher boiling point and the CaCl2 solution has the lower freezing point.
D) the CaCl2 solution has the higher boiling point and the NaCl solution has the lower freezing point.
E) both solutions have the same boiling point and the same freezing point.

Answer: B

How many milliliters of 0.755 M H2SO4 solution is needed to react with 55.0 mL of 2.50 M KOH solution?

Given 2 KOH (aq) + H2SO4 (aq) ? 2 H2O (l) + K2SO4 (aq)

A) 51.9 mL
B) 182 mL
C) 91.1 mL
D) 17200 mL
E) none of the above

Answer: C

How many mL of 0.218 M sodium sulfate react with exactly 25.34 mL of 0.113 M BaCl2 given the reaction

BaCl2(aq) + Na2SO4(aq) ? BaSO4(s) + 2NaCl (aq)

A) 13.1
B) 5.52
C) 24.6
D) 2.86
E) none of the above

Answer: A

What is the concentration of sodium chloride in the final solution if 25.34 mL of 0.113 M BaCl2 completely reacts and the total volume of the reaction is 110.4 mL, given the reaction

BaCl2(aq) + Na2SO4(aq) ? BaSO4(s) + 2NaCl (aq)

A) 0.226
B) 0.0259
C) 0.0519
D) 0.667
E) none of the above

Answer: C

How many grams of barium sulfate are produced if 25.34 mL of 0.113 M BaCl2 completely react given the reaction

BaCl2(aq) + Na2SO4(aq) ? BaSO4(s) + 2NaCl (aq)

A) 5.90
B) 26.3
C) 1039
D) 0.668
E) none of the above

Answer: D

How much water would you ADD to 175 mL of 6.00 M hydrochloric acid to prepare a 2.00 M solution of this acid?

A) 525 mL
B) 350 mL
C) 58.3 mL
D) 700. mL
E) none of the above

Answer: B

If you add 4.00 mL of pure water to 6.00 mL of 0.750 M NaCl solution, what is the concentration of sodium chloride in the diluted solution?

A) 0.250 M
B) 0.450 M
C) 0.500 M
D) 1.13 M
E) none of the above

Answer: B

What molarity should the stock solution be if you want to dilute 25.0 mL to 2.00 L and have the final concentration be 0.103 M?

A) 0.206 M
B) 8.24 M
C) 4.12 M
D) 0.243 M
E) none of the above

Answer: B

What volume of 9.00 M nitric acid is needed to make 6.50 L of 1.25 M solution?

A) 903 mL
B) 1.73 L
C) 1.10 L
D) 748 mL
E) none of the above

Answer: A

What volume of 12.0 M HCl is required to make 75.0 mL of 3.50 M HCl?

A) 21.9 mL
B) 0.560 mL
C) 257 mL
D) 560. mL
E) none of the above

Answer: A

What is the final concentration of a solution prepared by diluting 35.0 mL of 12.0 M HCl to a final volume of 1.20 L?

A) 0.504 M
B) 3.50 M
C) 0.420 M
D) 0.350 M
E) none of the above

Answer: D

A 90.0 g sample of NaOH is dissolved in water and the solution is diluted to give a final volume of 3.00 liters. The molarity of the final solution is ________.

A) 0.500 M
B) 0.750 M
C) 1.00 M
D) 2.25 M
E) none of the above

Answer: B

After you have completed the task of diluting a solution, which statement below must be TRUE?

A) The new solution has more volume but has a lower concentration than before.
B) The new solution has more volume but has a higher concentration than before.
C) The new solution has less volume but has a lower concentration than before.
D) The new solution has less volume but has a higher concentration than before.
E) none of the above

Answer: A

How many liters of a 2.18 M solution can be made from 200.0 g K2S?

A) 0.832
B) 1.81
C) 0.252
D) 1.20
E) none of the above

Answer: A

Which solution below contains the highest total quantity of dissolved sodium ions?

A) 100. mL of 4.0 M NaCl
B) 75.0 mL of 3.0 M Na2SO4
C) 50.0 mL of 8.0 M NaOH
D) 50.0 mL of 2.0 M Na3PO4
E) none of the above

Answer: B

Which one of the following aqueous solutions would have the higher concentration of K+ (aq) ions? (Assume total solubility in water.)

A) 1.0 M KC2H3O2
B) 1.0 M KNO3
C) 1.0 M K2CO3
D) 1.0 M K3PO4
E) All of these solutions have the same concentration of K+ (aq).

Answer: D

What are the ion concentrations in a 0.12 M solution of AlCl3?

A) 0.36 M Al3+ ions and 0.12 M Cl- ions
B) 0.12 M Al3+ ions and 0.040 M Cl- ions
C) 0.12 M Al3+ ions and 0.36 M Cl- ions
D) 0.040 M Al3+ ions and 0.040 M Cl- ions
E) none of the above

Answer: C

A 0.15 M solution of BaCl2 contains

A) 0.15 M Ba2+ ions and 0.15 M Cl- ions.
B) 0.15 M Ba2+ ions and 0.30 M Cl- ions.
C) 0.30 M Ba2+ ions and 0.15 M Cl- ions.
D) 0.30 M Ba2+ ions and 0.30 M Cl- ions.
E) none of the above

Answer: B

Oftentimes solubility of a compound limits the concentration of the solution that can be prepared. Use the solubility data given with each compound shown below to determine which compound would allow the preparation of a 10.0 Molar solution.

A) AgNO3 (solubility = 122 g/100 g H2O)
B) KCl (solubility = 34.0 g/100 g H2O)
C) NaNO3 (solubility = 89.0 g/100 g H2O)
D) NH4Cl (solubility = 41.1 g/100 g H2O)
E) none of the above

Answer: C

What mass (in grams) of fructose (C6H12O6) is contained in 125 mL of a 0.500 M fructose solution?

A) 11.3
B) 11300
C) 721
D) 0.0625
E) 180.

Answer: A

How many grams of LiF would be present in 575 mL of 0.750 M LiF solution?

A) 11.2
B) 0.0338
C) 1.12 × 104
D) 19.9
E) 33.8

Answer: A

How many grams of KCl are needed to make 50.0 mL of 2.45 M KCl?

A) 9.13
B) 1.52
C) 91.3
D) 0.123
E) none of the above

Answer: A

What is the molarity of a solution prepared by dissolving 54.3 g of Ca(NO3)2 into 355 mL of water?

A) 0.331 M
B) 0.932 M
C) 0.117 M
D) 1.99 M
E) none of the above

Answer: B

How many moles of KOH are contained in 750. mL of 5.00 M KOH solution?

A) 6.67 mol
B) 3.75 × mol
C) 56.1 mol
D) 3.75 mol
E) none of the above

Answer: D

Given that you wished to use exactly 0.325 mole of NaCl to prepare a 2.50 M NaCl solution, how many milliliters of solution must you prepare?

A) 130. mL
B) 0.130 mL
C) 7.69 mL
D) 0.813 mL
E) none of the above

Answer: A

You need to prepare 2.00 L of 0.100 M Na2CO3 solution. The best procedure is to weigh out

A) 10.6 g Na2CO3 and add 2.00 L of water to it.
B) 21.2 g Na2CO3 and add 2.00 L of water to it.
C) 10.6 g Na2CO3 and add water until the final solution has a volume of 2.00 L.
D) 21.2 g Na2CO3 and add water until the final solution has a volume of 2.00 L.

Answer: D

What is the molarity of a solution prepared by dissolving 10.7g NaI in 0.250 L ?

A) 42.8
B) 0.0714
C) 2.86
D) 0.286
E) none of the above

Answer: D

How many moles of NaF are in 34.2 grams of a 45.5% by mass NaF solution?

A) 0.814
B) 75.2
C) 15.6
D) 0.371
E) none of the above

Answer: D

How many grams of a 23.4% by mass NaF solution is needed if you want to have 1.33 moles of NaF?

A) 55.9
B) 31.1
C) 13.1
D) 239
E) none of the above

Answer: D

What is the mass percent of a sodium fluoride solution prepared by dissolving 0.64 moles of sodium fluoride into 63.5 grams of water?

A) 26.9%
B) 42.3%
C) 70.3%
D) 29.7%
E) none of the above

Answer: D

What is the mass percent of an ammonium carbonate solution prepared by dissolving 33.2 grams of solid into 39.5 grams of water?

A) 84.1%
B) 72.7%
C) 45.7%
D) 54.3%
E) none of the above

Answer: C

What is the mass percent of a solution prepared by dissolving 18.9 grams of solid into 39.5 grams of water?

A) 47.8%
B) 58.4%
C) 32.4%
D) The identity of the compound must be known.
E) none of the above

Answer: C

A solution contains 100.0 g water, 10.0 g NaCl, and 15.0 g methanol. What is the mass percent of methanol in the solution?

A) 8.00%
B) 10.0%
C) 12.0%
D) 15.0%
E) none of the above

Answer: C

We dissolve 2.45 g of sugar in 200.0 g water. What is the mass percent of sugar in the solution?

A) 1.21%
B) 1.23%
C) 2.42%
D) 123%
E) none of the above

Answer: A

When preparing sodium hydroxide solution, it is best to use water that does not contain any dissolved carbon dioxide as it reacts with the sodium hydroxide. Removing the carbon dioxide can be accomplished by

A) vigorously stirring the solution.
B) using water fresh out of the purification system.
C) boiling the water.
D) Nothing can be done to remove dissolved gases.
E) none of the above

Answer: C

A solution is saturated in both nitrogen gas (N2) and sodium iodide (NaI) at 50°C. When the solution is cooled to 25°C, which of the following is most likely to occur?

A) Some nitrogen gas bubbles out of solution.
B) Some sodium iodide will precipitate out of solution.
C) Both A and B will happen.
D) Nothing will happen.
E) not enough information

Answer: B

The solubility of a gas in a liquid can always be increased by

A) increasing the temperature of the solvent.
B) decreasing the polarity of the solvent.
C) decreasing the pressure of the gas above the solvent.
D) increasing the pressure of the gas above the solvent.
E) none of the above

Answer: D

The solubility of gases in water

A) is independent of temperature.
B) increases with increasing temperature.
C) decreases with increasing temperature.
D) gases are not soluble in water.
E) none of the above

Answer: C

Solubility of gases in water

A) is independent of pressure above solution.
B) increases with increasing pressure above solution.
C) decreases with increasing pressure above solution.
D) Gases are not soluble in water.
E) none of the above

Answer: B

Which among the following is NOT true about the solubility of a solid in water?

A) The solubility is not affected by pressure.
B) The solubility generally increases as temperature increases.
C) Solid crystallizes when a saturated solution is prepared at a higher temperature and then cooled.
D) A saturated solution prepared at a lower temperature becomes unsaturated when heated to a higher temperature.
E) none of the above

Answer: E

When an ionic compound dissolves in water

A) the solvent-solute attractive forces overcome the solute-solute attractions.
B) the positive end of water dipoles attract the negative ions.
C) the negative end of water dipoles attract the positive ions.
D) each of the above (A, B, and C) occurs.
E) none of the above (A, B, or C) occurs.

Answer: D

The solubility of solids in water

A) is independent of pressure above solution.
B) increases with increasing pressure above solution.
C) decreases with increasing pressure above solution.
D) Solids are not soluble in water.
E) none of the above

Answer: A

The solubility of solids in water

A) is independent of the temperature.
B) increases with increasing temperature.
C) decreases with increasing temperature.
D) Solids are not soluble in water.
E) none of the above

Answer: B

Which of the following compounds is a strong electrolyte?

A) C6H12O6
B) C7H14O5
C) C4H8O2
D) NaC2H3O2
E) all of the above

Answer: D

Which of the following compounds is a strong electrolyte?

A) HCl
B) NaCl
C) NH4Cl
D) NaC2H3O2
E) all of the above

Answer: E

If you prepare a solution by adding sufficient amount of solute so that after heating and cooling the solution there is a visible amount of solid solute left in the bottom of the beaker, the solution would be considered ________.

A) unsaturated
B) saturated
C) supersaturated
D) thermally saturated
E) none of the above

Answer: B

The solubility of Pb(NO3)2 is 55 grams per 100 g H2O at 20°C. Which term would properly describe a solution where 44 grams of Pb(NO3)2 is added to 100 grams of water at this temperature?

A) insoluble
B) unsaturated
C) saturated
D) supersaturated
E) none of the above

Answer: B

If the solubility of sodium chloride is 36 grams per 100 grams of water, which of the following solutions would be considered unsaturated?

A) 5.8 moles of NaCl dissolved in 1 L of water
B) 3.25 moles of NaCL dissolved in 500 ml of water
C) 1.85 moles of NaCl dissolved in 300 ml of water
D) none of the above

Answer: A

If the solubility of sodium acetate (Molar mass = 82 g/mol) is 76 grams per 100 grams of water, which of the following solutions would be considered supersaturated?

A) 8.5 moles of sodium acetate dissolved in 1 L of water
B) 5.5 moles of sodium acetate dissolved in 500 mL of water
C) 1.8 moles of sodium acetate dissolved in 300 mL of water
D) 1.2 moles of sodium acetate dissolved in 200 mL of water
E) none of the above

Answer: B

In order for a solute to dissolve in solution

A) the solute-solvent forces must be greater than the solute-solute forces.
B) the solute-solute forces must be greater than the solute-solvent forces.
C) the solute-solvent forces must equal the solute-solute forces.
D) the polarity of the solute and solvent must be opposite.
E) none of the above

Answer: A

Which compound below forms an electrolyte solution when dissolved in water?

A) Cl2
B) KOH
C) CH3CH2OH
D) C12H22O11 (sucrose)
E) none of the above

Answer: B

Which of these compounds would you expect to be least soluble in water?

A) CH3OH
B) NaCl
C) N2
D) NH3
E) not enough information

Answer: C

Hexane, a nonpolar solvent, will dissolve which of the following substances?

A) sodium chloride
B) oil
C) ammonium acetate
D) vinegar (acetic acid)
E) none of the above

Answer: B

The oxygen in the air we breath is classified as

A) the solute in a homogeneous gas mixture.
B) the solvent in a homogeneous gas mixture.
C) the solute in a heterogeneous gas-liquid mixture.
D) the solvent in a simple mixture.
E) none of the above

Answer: A

Suppose a vodka martini contains 30% alcohol with the remaining portion of the drink composed of water. What is the solute in this type of martini?

A) water
B) alcohol
C) ice
D) olive
E) none of the above

Answer: B

Which of the following substances is NOT a solution?

A) homogenized milk
B) bronze
C) sea water
D) soda
E) All of the above are solutions.

Answer: E

Which of the following substances is NOT a solution?

A) humid air
B) beer
C) oxygen
D) steel
E) All of the above are solutions.

Answer: C

Which of the following substances is NOT a solution?

A) air
B) brass
C) vodka
D) copper
E) All of the above are solutions.

Answer: D

The tragedy at Lake Nyos in Cameroon, West Africa, was caused by

A) the release of excessive amounts of nitrogen gas that had been dissolved in the water at the bottom of the lake.
B) the release of excessive amounts of oxygen gas that had been dissolved in the water at the bottom of the lake.
C) the release of excessive amounts of carbon dioxide that had been dissolved in the water at the bottom of the lake.
D) the release of excess water stored in the volcanic lake which flooded the village below.
E) none of the above

Answer: C

What is the mass percent of oxygen in sodium oxide?

A) 37.1
B) 25.8
C) 74.2
D) 62.0
E) none of the above

Answer: B

What is the mass percent of Na in sodium chloride?

A) 58.4
B) 60.7
C) 39.3
D) 47.5
E) none of the above

Answer: C

Given that sodium chloride is 39.0% sodium by mass, how many grams of sodium chloride are needed to have 950 mg of Na present?

A) 2.44
B) 0.371
C) 2,430
D) 37.1
E) none of the above

Answer: A

How many moles of oxygen are in 3.30 moles of NaClO4 ?

A) 3.30
B) 0.303
C) 19.0
D) 13.2
E) none of the above

Answer: D

What is the mass (in grams) of 3.03 × 1024 molecules of carbon dioxide molecules?

A) 221
B) 0.114
C) 1.33
D) 44.01
E) none of the above

Answer: A

What is the mass (in grams) of 1.95 moles of water ?

A) 18.02
B) 9.24
C) 35.1
D) 6.022 × 10 23
E) none of the above

Answer: C

How many atoms of lithium are in 18.7 g?

A) 2.14 x 1024
B) 2.70 x 1024
C) 1.62 x 1024
D) 3.11 x 1024
E) none of the above

Answer: C

What is the mass of 3.91 x 1024 sulfur atoms?

A) 208
B) 4.93
C) 155
D) 32.07
E) none of the above

Answer: A

How many moles of potassium are in 156.4 g?

A) 39.10
B) 4.000
C) 0.2500
D) 5.050
E) none of the above

Answer: B

If you have 2.41 x 1024 atoms of copper, how many moles of copper do you have?

A) 0.250
B) 4.00
C) 0.600
D) 3.00
E) none of the above

Answer: B

How many atoms are present in 4.5 moles?

A) 3.7 x 1023
B) 3.7 x 10-25
C) 2.7 x 1024
D) 6.02 x 1023
E) none of the above

Answer: C

Bananas cost 33¢ per pound. If you spent $0.77, how many pounds of bananas did you purchase?

A) 2.33
B) 1.73
C) 0.429
D) 2.01
E) none of the above

Answer: A

A compound composed of only hydrogen and oxygen is 5.94% hydrogen by mass. The molar mass of this compound is 34.02 g/mol. What is the compound's molecular formula?

A) 34.02
B) H2O2
C) HO
D) H6O
E) none of the above

Answer: B

An unknown acid has a molar mass of 60.06 g/mol. Given the following percent composition, what is the molecular formula? 40% C, 6.7% H, 53.3% O .

A) C3H4O3
B) CH2O
C) C2H4O2
D) C6H12O6
E) none of the above

Answer: C

A compound has a molar mass of 180.18 g/mol. Given the following percent composition, calculate the molecular formula: 39.99% C, 6.73% H, 53.28% O.

A) CH3O2
B) CH2O
C) C3H6O3
D) C6H12O6
E) none of the above

Answer: D

What is the molecular formula of a compound given the molar mass of the compound is 30.04 gram and the empirical formula is NH?

A) NH
B) N2H2
C) N2H6
D) N4H4
E) none of the above

Answer: B

What would the empirical formula be for the molecular compound C6H9O4?

A) C2H3O2
B) CH3O2
C) C3H6O2
D) C3H9O4
E) none of the above

Answer: E

What is the value of n when the empirical formula is C3H5 and the molecular mass is 205.4 g/mol?

A) 0.02
B) 5
C) 10
D) 140
E) none of the above

Answer: B

An estrogen compound with the empirical formula C12H17O2 has a molecular mass of 386.6 g/mol. What is the value of n necessary to find the molecular formula?

A) 0.2
B) 1
C) 2
D) 20
E) none of the above

Answer: C

What is the molecular formula of a compound given the molar mass of the compound is 186.5 gram and the empirical formula is C2H7?

A) C4H14
B) C3H21
C) C2H7
D) C2H14
E) none of the above

Answer: E

A compound composed of only carbon and hydrogen is 25.2% hydrogen by mass. The empirical formula for this compound is:

A) CH 0.25
B) C3H
C) CH4
D) C2H8
E) none of the above

Answer: C

Determine the correct empirical formula of a compound containing 26.68% carbon, 2.24% hydrogen, and 71.08% oxygen.

A) CHO
B) CHO2
C) C0.5H0.5O1
D) C2H2O4
E) none of the above

Answer: B

Vitamin C is known chemically by the name ascorbic acid. Determine the empirical formula of ascorbic acid if it is composed of 40.92% carbon, 4.58% hydrogen, and 54.50% oxygen.

A) CHO
B) CH2O
C) C2H3O2
D) C3H4O3
E) none of the above

Answer: D

Determine the empirical formula of a compound containing 83% potassium and 17.0% oxygen.

A) KO
B) KO2
C) K2O3
D) K2O
E) none of the above

Answer: D

Determine the empirical formula of a compound containing 60.3% magnesium and 39.7% oxygen.

A) MgO
B) MgO2
C) Mg2O3
D) Mg2O
E) none of the above

Answer: A

A 7.96 gram sample of silver reacts with oxygen to form 8.55 gram of the metal oxide. What is the formula of the oxide?

A) AgO
B) AgO2
C) Ag2O
D) Ag3O
E) none of the above

Answer: C

An iron chloride compound contains 55.85 grams of iron and 106.5 grams of chlorine. What is the most likely empirical formula for this compound?

A) FeCl
B) FeCl2
C) Fe2Cl
D) FeCl3
E) Fe3Cl

Answer: D

A chromium oxide compound contains 104.0 grams of chromium and 48.0 grams of oxygen. What is the most likely empirical formula of this compound?

A) CrO
B) CrO2
C) CrO3
D) Cr2O3
E) Cr3O2

Answer: D

The chemical formula CH2O can be classified as:

A) molecular only.
B) empirical only.
C) empirical, possibly molecular.
D) not enough information
E) none of the above

Answer: C

Which of the following is already in its empirical formula?

A) C22H34O10
B) C6H6
C) C6H12O3
D) C5H12O2
E) none of the above

Answer: D

The simplest formula for hydrogen peroxide is HO. To determine its molecular formula, it is necessary to know:

A) the properties of hydrogen peroxide.
B) the density of hydrogen peroxide.
C) the molar mass of hydrogen peroxide.
D) the number of moles of hydrogen peroxide in 1.00 g of the substance.
E) none of the above

Answer: C

The empirical formula of a compound:

A) describes the mass relationships in a molecule.
B) is the same as the molecular formula.
C) indicates the structure of the molecule.
D) indicates the simplest ratio of atoms in the compound.
E) none of the above

Answer: D

Which of the following statements about empirical formulas is incorrect?

A) An empirical formula represents a molecule.
B) An empirical formula gives the smallest whole number ratio of each type of atom in a molecule.
C) An empirical formula must be multiplied by an integer to obtain the molecular formula.
D) The molecular formula can be the same as the empirical formula in some situations.
E) All statements are correct.

Answer: A

Which of the following compounds has the highest mass percent of "O"?

A) MnO
B) MnO2
C) Mn2O3
D) Mn3O2
E) none of the above

Answer: B

What is the mass percent of carbon in oxalic acid, H2C2O4?

A) 2.24
B) 13.3
C) 26.7
D) 34.5
E) none of the above

Answer: C

What is the mass percent of chlorine in hydrochloric acid?

A) 2.8
B) 35.5
C) 97.2
D) 70.1
E) none of the above

Answer: C

What is the mass percent of hydrogen in water?

A) 33.3
B) 88.8
C) 5.60
D) 11.2
E) none of the above

Answer: D

Bauxite is an ore that contains the element aluminum. If you obtained 108 grams of aluminum from an ore sample that initially weighed 204 grams, what is the mass percent of aluminum in this bauxite ore?

A) 52.9
B) 15.6
C) 0.53
D) 47.1
E) none of the above

Answer: A

A 500. gram iron ore sample was determined to contain 242 grams of iron. What is the mass percent of iron in the ore?

A) 93.7
B) 48.4
C) 51.6
D) 32.6
E) none of the above

Answer: B

An iron ore sample is found to be 35.00% Fe by mass. How many grams of ore are needed to obtain 454.0 grams of Fe?

A) 1297
B) 158.9
C) 295.1
D) 350.0
E) none of the above

Answer: A

A 42.7 gram sample of potassium nitrate contains how many grams of potassium?

A) 39.1
B) 16.5
C) 21.4
D) 8.54
E) none of the above

Answer: B

A 15.5 gram sample of diphosphorus pentoxide contains how many grams of phosphorous?

A) 3.38
B) 1.69
C) 6.76
D) 13.5
E) none of the above

Answer: C

If a sample of carbon dioxide contains 3.8 moles of oxygen atoms, how many moles of carbon dioxide are in the sample?

A) 1.9
B) 3.8
C) 7.6
D) 11.4
E) none of the above

Answer: A

How many moles of fluorine are in 3.2 moles of xenon hexafluoride?

A) 22.4
B) 12.8
C) 19.2
D) 16
E) none of the above

Answer: C

How many moles of carbon are in 3.5 moles of calcium carbonate?

A) 10.5
B) 3.5
C) 7
D) 100.09
E) none of the above

Answer: B

One mole of potassium sulfate contains:

A) 4 moles of oxygen.
B) 2 moles of sulfur.
C) 1 mole of potassium.
D) 3 moles of potassium.
E) none of the above

Answer: A

One mole of ammonium nitrite contains:

A) 2 moles of nitrogen atoms.
B) 4 moles of hydrogen atoms.
C) 2 moles of oxygen atoms.
D) All of A, B, and C.
E) None of A, B, and C.

Answer: D

One mole of ammonium nitrate contains:

A) 3 moles of hydrogen.
B) 2 moles of oxygen.
C) 2 moles of nitrogen.
D) 1 mole of nitrogen.
E) none of the above

Answer: C

One mole of (NH4)2HPO4 contains how many moles of hydrogen atoms?

A) 4
B) 2
C) 8
D) 9
E) none of the above

Answer: D

If 2.01 × 10^23 atoms of an element from Group IA of the periodic table has a mass of 7.675 grams, this element is most likely:

A) Li.
B) Na.
C) K.
D) Rb.
E) Cs.

Answer: B

If 3.011 × 10^23 molecules have a mass of 20.04 grams, what is the molar mass of this substance?

A) 40.08 g/mol
B) 10.02 g/mol
C) 20.04 g/mol
D) 6.658 × 10^-23g/mol
E) none of the above

Answer: A

How many molecules of nitrogen monoxide are in a 22.5 gram sample?

A) 5.86 × 10^23
B) 7.33 × 10^23
C) 4.51 × 10^23
D) 4.06 × 10^23
E) none of the above

Answer: C

How many molecules of sulfur trioxide are in 78.0 grams?

A) 5.87 × 1023
B) 7.33 × 1023
C) 3.76 × 1027
D) 0.974
E) none of the above

Answer: A

Calculate the molar mass of calcium nitrate.

A) 136.03 g/mol
B) 102.09 g/mol
C) 132.10 g/mol
D) 164.10 g/mol
E) none of the above

Answer: D

Calculate the molar mass of ammonium carbonate.

A) 78.05 g/mol
B) 88.05 g/mol
C) 96.09 g/mol
D) 112.09 g/mol
E) none of the above

Answer: C

What is the molar mass of aluminum sulfate?

A) 123.0 g/mol
B) 278.0 g/mol
C) 306.2 g/mol
D) 315.2 g/mol
E) 342.2 g/mol

Answer: E

The mass of one mole of carbon dioxide is ________ g.

A) 28.01
B) 384.4
C) 32.00
D) 44.01
E) none of the above

Answer: D

Which of the following contains 9.02 × 10^23 atoms?

A) 4.00 g H2
B) 9.00 g H2O
C) 28.0 g N2
D) 32.0 g O2
E) none of the above

Answer: B

In comparing 1 mole of carbon atoms to one mole of magnesium atoms, which statement is TRUE?

A) The mass of 1 mole of carbon is greater than the mass of 1 mole of magnesium.
B) The mass of 1 mole of magnesium is greater than the mass of 1 mole of carbon.
C) The mass of 1 mole of carbon is the same as the mass of 1 mole of magnesium.
D) There are more atoms in 1 mole of magnesium than in 1 mole of carbon.
E) none of the above

Answer: B

In comparing a balloon containing 25 grams of helium to a balloon containing 25 grams of neon, which one of the following statements is TRUE?

A) Each balloon has an equal number of atoms.
B) The helium balloon has more atoms.
C) The neon balloon has more atoms.
D) This scenario cannot happen because gases have no mass.
E) none of the above

Answer: B

What is the mass of 1.56 × 10^21 atoms of magnesium in grams?

A) 4.72 × 10^-5
B) 0.0630
C) 0.142
D) 1.07 × 10^-4
E) none of the above

Answer: B

How many moles of Pb are in 4.71 × 1021 Pb atoms?

A) 0.00782
B) 2.84 × 10^45
C) 207.2
D) 6.022 × 10^23
E) none of the above

Answer: A

What is the mass of 3.09 × 10^24 atoms of sulfur in grams?

A) 9.64 × 10^22
B) 9.91 × 10^25
C) 165
D) 0.160
E) none of the above

Answer: C

How many hydrogen atoms are in 35.0 grams of hydrogen gas?

A) 4.25 × 10^25
B) 2.09 × 10^25
C) 2.12 × 10^25
D) 1.05 × 10^25
E) none of the above

Answer: D

How many atoms are in 15.6 grams of silicon?

A) 2.64 × 10^26
B) 3.34 × 10^23
C) 0.555
D) 438
E) none of the above

Answer: B

How many moles of bromine gas are in 37.7 grams?

A) 0.236
B) 0.472
C) 3.01 × 103
D) 79.9
E) none of the above

Answer: A

How many moles are there in 82.5 grams of iron?

A) 4.97 × 10^25
B) 55.85
C) 0.677
D) 1.48
E) none of the above

Answer: D

How many moles are there in 17.5 grams of sodium?

A) 22.99
B) 1.05 × 10^25
C) 0.761
D) 1.31
E) none of the above

Answer: C

How many moles of iron are contained in 1.75 kg of iron?

A) 3.13 × 10^-2
B) 3.13 × 10^-4
C) 31.3
D) 3.13 × 10^4
E) none of the above

Answer: C

You have 10.0 g each of Na, C, Pb, Cu and Ne. Which contains the smallest number of moles?

A) Na
B) C
C) Pb
D) Cu
E) Ne

Answer: C

You have 10.0 g each of Na, C, Pb, Cu and Ne. Which contains the largest number of moles?

A) Na
B) C
C) Pb
D) Cu
E) Ne

Answer: B

What is the mass of 0.560 moles of chlorine gas?

A) 19.9
B) 63.3
C) 127
D) 39.7
E) none of the above

Answer: D

What is the mass in grams of 5.40 moles of lithium?

A) 6.94
B) 37.5
C) 1.29
D) 3.25 × 10^24
E) none of the above

Answer: B

One mole of oxygen gas has a mass of ________ g.

A) 16.0
B) 32.0
C) 6.022 × 1023
D) 8
E) none of the above

Answer: B

One mole of boron has a mass of ________ g.

A) 9.012
B) 6.022 × 10^23
C) 5
D) 10.811
E) none of the above

Answer: D

How many moles of Cu are in 1.48 × 10^25 Cu atoms?

A) 0.0408
B) 24.6
C) 1.54 × 10^25
D) 6.022 × 10^23
E) none of the above

Answer: B

How many atoms are in 1.50 moles of fluorine gas?

A) 6.022 × 10^23
B) 9.03 × 10^23
C) 18.98
D) 1.81 × 10^24
E) none of the above

Answer: D

How many atoms are in 5.80 moles of He?

A) 6.02 × 10^23
B) 1.03 × 10^23
C) 4.00
D) 3.49 × 10^24
E) none of the above

Answer: D

Which of the following statements about the mole is FALSE?

A) One mole of atoms makes up an amount of atoms that can be seen with the naked eye.
B) A mole of a monatomic element corresponds to one Avogadro's number of atoms.
C) One mole of a monatomic element has a mass equal to its atomic mass expressed in grams.
D) One mole of water contains 1/2 mole of oxygen atoms.
E) none of the above

Answer: D

One half of a mole of atoms would contain how many atoms?

A) 0.5
B) 3.011 × 10^23
C) 6.022 × 10^23
D) 6.022 × 10^11.5
E) none of the above

Answer: B

What is the correct value for Avogadro's number?

A) 6.022 × 10^23
B) 6.022 × 10^33
C) 6.023 × 10^22
D) 6.022 × 10^2.3
E) none of the above

Answer: A

Hydrochloric acid reacts with barium hydroxide according to the equation: 2 HCl (aq) + Ba(OH)2 (aq) > BaCl2 (aq) + 1H2O (l) H= -118 kj Calculate the heat (in kJ) associated with the complete reaction of 18.2 grams of HCl (aq).

Hydrochloric acid reacts with barium hydroxide according to the equation:
2 HCl (aq) + Ba(OH)2 (aq) > BaCl2 (aq) + 1H2O (l) H= -118 kj
Calculate the heat (in kJ) associated with the complete reaction of 18.2 grams of HCl (aq).

A) -58.9
B) +58.9
C) -29.5
D) -236
E) none of the above

Answer: C

Starting with 156 g Li2O and 33.3 g H2O, decide which reactant is present in limiting quantities. Given: Li2O + H2O ? 2 LiOH

Starting with 156 g Li2O and 33.3 g H2O, decide which reactant is present in limiting quantities.
Given: Li2O + H2O ? 2 LiOH

A) lithium oxide
B) water
C) lithium hydroxide
D) insufficient data
E) none of the above

Answer: B

Consider a reaction of chemicals depicted as A + B ? C + D. Suppose reaction of 17.8 grams of A with 29.5 grams of B gave 24.7 grams of C. However, the theoretical yield of C for this reaction was 33.3 grams. What was the percent yield of chemical C?

A) 74.2
B) 47.3
C) 11.7
D) 135
E) none of the above

Answer: A

If the theoretical yield of the reaction below corresponds to 25.3 g and the percent yield of the reaction is known to be reproducibly 81.1%, calculate the actual yield. Given: Li2O + H2O ? 2 LiOH

If the theoretical yield of the reaction below corresponds to 25.3 g and the percent yield of the reaction is known to be reproducibly 81.1%, calculate the actual yield.
Given: Li2O + H2O ? 2 LiOH

A) 20.5 g
B) 48.9 g
C) 45.8 g
D) 81.1 g
E) none of the above

Answer: A

If the theoretical yield of the reaction below corresponds to 99.2 g and the actual yield was 60.9 g, calculate the percent yield. Given: Li2O +H2O ? 2 LiOH

If the theoretical yield of the reaction below corresponds to 99.2 g and the actual yield was 60.9 g, calculate the percent yield.
Given: Li2O +H2O ? 2 LiOH

A) 16.0 %
B) 71.8 %
C) 38.0 %
D) 61.4 %
E) none of the above

Answer: D

How many grams of water are needed to react with 27.2 grams of O? Given: Li2O + H2O ? 2 LiOH

How many grams of water are needed to react with 27.2 grams of O?
Given: Li2O + H2O ? 2 LiOH

A) 0.910
B) 16.4
C) 1.51
D) 38.94
E) none of the above

Answer: B

How many moles of water are needed to react with 2.2 moles of Li2O? Given: Li2O + H2O ? 2 LiOH

How many moles of water are needed to react with 2.2 moles of Li2O?
Given: Li2O + H2O ? 2 LiOH

A) 4.4
B) 1.1
C) 1.5
D) 2.2
E) none of the above

Answer: D

Suppose a computer manufacturer can build circuit boards according to the following process: 12 resistors + 20 insulators + 8 memory chips ? 4 circuit boards. How many circuit boards could you make using 30 insulators, assuming you have enough of all the other parts?

Suppose a computer manufacturer can build circuit boards according to the following process:
12 resistors + 20 insulators + 8 memory chips ? 4 circuit boards.
How many circuit boards could you make using 30 insulators, assuming you have enough of all the other parts?

A) 20
B) 4
C) 10
D) 6
E) none of the above

Answer: D

Consider the following equation: CO + 2 H2 ? CH3OH ?H rxn = -128 kJ Calculate the amount of heat (in kJ) associated with complete reaction of 8.08 g H2.

Consider the following equation: CO + 2 H2 ? CH3OH ?H rxn = -128 kJ
Calculate the amount of heat (in kJ) associated with complete reaction of 8.08 g H2.

A) -1024 kJ
B) -1034 kJ
C) -256 kJ
D) -512 kJ
E) none of the above

Answer: C

Consider the following reaction: 2 Mg + O2 ? 2 MgO ?H rxn = -1203 kJ Calculate the amount of heat (in kJ) associated with complete reaction of 4 moles of Mg.

Consider the following reaction: 2 Mg + O2 ? 2 MgO ?H rxn = -1203 kJ
Calculate the amount of heat (in kJ) associated with complete reaction of 4 moles of Mg.

A) -1203 kJ
B) -2406 kJ
C) -601.5 kJ
D) -4812 kJ
E) none of the above

Answer: B

The reaction of one mole of nitrogen gas with three moles of hydrogen gas releases 92 kJ of thermal energy to the surroundings. Which of the following is TRUE?

A) This reaction is exothermic.
B) This reaction has a negative enthalpy of reaction.
C) Complete reaction of two moles of nitrogen gas would release 184 kJ of thermal energy in this reaction.
D) All of the above are true.
E) None of the above are true.

Answer: D

Consider the reaction: 2 Al + 3Br2 ? 2 AlBr3 Suppose a reaction vessel initially contains 5.0 mole Al and 6.0 mole Br2. What is in the reaction vessel once the reaction has occurred to the fullest extent possible?

Consider the reaction: 2 Al + 3Br2 ? 2 AlBr3
Suppose a reaction vessel initially contains 5.0 mole Al and 6.0 mole Br2. What is in the reaction vessel once the reaction has occurred to the fullest extent possible?

A) 1.0 mole Al; 0 mole Br2; 4.0 mole AlBr3
B) 0 mole Al; 0 mole Br2; 11.0 mole AlBr3
C) 2.0 mole Al; 3.0 mole Br2; 2.0 mole AlBr3
D) 0 mole Al; 1.0 mole Br2; 4.0 mole AlBr3
E) none of the above

Answer: A

How many grams of the excess reactant remain assuming the reaction goes to completion and that you start with 15.5 g of Na2S and 12.1 g CuSO4? Reaction: Na2S + CuSO4 ? Na2SO4 + CuS

How many grams of the excess reactant remain assuming the reaction goes to completion and that you start with 15.5 g of Na2S and 12.1 g CuSO4?
Reaction: Na2S + CuSO4 ? Na2SO4 + CuS

A) 0.05
B) 15.45
C) 9.58
D) 5.92
E) not enough information

Answer: C

What is the percent yield of CuS for the following reaction given that you start with 15.5 g of Na2S and 12.1 g CuSO4? The actual amount of CuS produced was 3.05. Reaction: Na2S + CuSO4 ? Na2SO4 + CuS

What is the percent yield of CuS for the following reaction given that you start with 15.5 g of Na2S and 12.1 g CuSO4? The actual amount of CuS produced was 3.05.
Reaction: Na2S + CuSO4 ? Na2SO4 + CuS

A) 16.1%
B) 42.1%
C) 18.93%
D) 7.25%
E) not enough information

Answer: B

What is the theoretical yield in grams of CuS for the following reaction given that you start with 15.5 g of Na2S and 12.1 g CuSO4? Reaction: Na2S + CuSO4 ? Na2SO4 + CuS

What is the theoretical yield in grams of CuS for the following reaction given that you start with 15.5 g of Na2S and 12.1 g CuSO4?
Reaction: Na2S + CuSO4 ? Na2SO4 + CuS

A) 0.0758
B) 0.198
C) 18.93
D) 7.25
E) not enough information

Answer: D

Which is the limiting reactant in the following reaction given that you start with 42.0 g of CO2 and 99.9 g KOH? Reaction: CO2 + 2KOH ? K2CO3 + H2O

Which is the limiting reactant in the following reaction given that you start with 42.0 g of CO2 and 99.9 g KOH?
Reaction: CO2 + 2KOH ? K2CO3 + H2O

A) K2CO3
B) H2O
C) CO2
D) KOH
E) not enough information

Answer: D

Which is the limiting reactant in the following reaction given that you start with 15.5 g of Na2S and 12.1 g CuSO4? Reaction: Na2S + CuSO4 ? Na2SO4 + CuS

Which is the limiting reactant in the following reaction given that you start with 15.5 g of Na2S and 12.1 g CuSO4?
Reaction: Na2S + CuSO4 ? Na2SO4 + CuS

A) Na2S
B) CuSO4
C) Na2SO4
D) CuS
E) not enough information

Answer: B

Which is the excess reactant in the following reaction given that you start with 15.5 g of Na2S and 12.1 g CuSO4? Reaction: Na2S + CuSO4 ? Na2SO4 + CuS

Which is the excess reactant in the following reaction given that you start with 15.5 g of Na2S and 12.1 g CuSO4?
Reaction: Na2S + CuSO4 ? Na2SO4 + CuS

A) Na2S
B) CuSO4
C) Na2SO4
D) CuS
E) not enough information

Answer: A

A 24.0 g sample of nitrogen gas reacts with an excess of hydrogen gas to give an actual yield of 3.85 g NH3. What is the percent yield for this reaction? Reaction: N2(g) + 3 H2(g) ? 2 NH3(g)

A 24.0 g sample of nitrogen gas reacts with an excess of hydrogen gas to give an actual yield of 3.85 g NH3. What is the percent yield for this reaction?
Reaction: N2(g) + 3 H2(g) ? 2 NH3(g)

A) 86.8%
B) 73.6%
C) 26.4%
D) 13.2%
E) none of the above

Answer: D

Calculate the maximum number of grams of NH3 that can be produced by the reaction of 2.00 g of N2 with 3.00 g H2. Reaction: N2(g) + 3 H2(g) ? 2 NH3(g)

Calculate the maximum number of grams of NH3 that can be produced by the reaction of 2.00 g of N2 with 3.00 g H2.
Reaction: N2(g) + 3 H2(g) ? 2 NH3(g)

A) 0.964
B) 2.43
C) 4.00
D) 17.0
E) none of the above

Answer: B

How many moles of NH3 can be produced by the reaction of 2.00 g of N2 with 3.00 g H2? Reaction: N2(g) + 3 H2(g) ? 2 NH3(g)

How many moles of NH3 can be produced by the reaction of 2.00 g of N2 with 3.00 g H2?
Reaction: N2(g) + 3 H2(g) ? 2 NH3(g)

A) 0.143
B) 0.0567
C) 0.235
D) 1.00
E) none of the above

Answer: A

How many grams of the excess reactant are left over according to the reaction below given that you start with 10.0 g of Al and 19.0 grams of O2? Reaction: 4Al + 3O2 ? 2Al2O3

How many grams of the excess reactant are left over according to the reaction below given that you start with 10.0 g of Al and 19.0 grams of O2?
Reaction: 4Al + 3O2 ? 2Al2O3

A) 8.90
B) 10.1
C) 1.1
D) 14.6
E) not enough information

Answer: B

The reaction for the oxidation of NH3 is given as: 4 NH3 + 5 O2 ? 4 NO + 6 H2O Under certain conditions the reaction will proceed at 29.8% yield of NO. How many grams of NH3 must be made to react with excess oxygen to yield 70.5 g of NO?

The reaction for the oxidation of NH3 is given as:
4 NH3 + 5 O2 ? 4 NO + 6 H2O
Under certain conditions the reaction will proceed at 29.8% yield of NO. How many grams of NH3 must be made to react with excess oxygen to yield 70.5 g of NO?

A) 134
B) 237
C) 21.0
D) 2.37
E) none of the above

Answer: A

A sample of 8.5 g NH3 on oxidation produces 4.5 g of NO. Calculate the percent yield. Reaction: 4 NH3 + 5 O2 ? 4 NO + 6 H2O

A sample of 8.5 g NH3 on oxidation produces 4.5 g of NO. Calculate the percent yield.
Reaction: 4 NH3 + 5 O2 ? 4 NO + 6 H2O

A) 15 %
B) 30%
C) 60%
D) 70%
E) none of the above

Answer: B

If 16.0 grams of aluminum oxide were actually produced, what is the percent yield of the reaction below given that you start with 10.0 g of Al and 19.0 grams of O2? Reaction: 4Al + 3O2 ? 2Al2O3

If 16.0 grams of aluminum oxide were actually produced, what is the percent yield of the reaction below given that you start with 10.0 g of Al and 19.0 grams of O2?
Reaction: 4Al + 3O2 ? 2Al2O3

A) 75.0%
B) 100%
C) 84.7%
D) 39.6%
E) not enough information

Answer: C

How many grams of aluminum oxide are produced according to the reaction below given that you start with 10.0 grams of Al and 19.0 grams of O2? Reaction: 4Al + 3O2 ? 2Al2O3

How many grams of aluminum oxide are produced according to the reaction below given that you start with 10.0 grams of Al and 19.0 grams of O2?
Reaction: 4Al + 3O2 ? 2Al2O3

A) 40.4
B) 5.00
C) 0.185
D) 18.9
E) not enough information

Answer: D

How many moles of aluminum oxide are produced according to the reaction below given that you start with 10.0 grams of Al and 19.0 grams of O2? Reaction: 4Al + 3O2 ? 2Al2O3

How many moles of aluminum oxide are produced according to the reaction below given that you start with 10.0 grams of Al and 19.0 grams of O2?
Reaction: 4Al + 3O2 ? 2Al2O3

A) 0.396
B) 0.185
C) 0.741
D) 5.00
E) not enough information

Answer: B

What is the excess reactant for the reaction below given that you start with 10.0 grams of Al and 19.0 grams of O2? Reaction: 4Al + 3O2 ? 2Al2O3

What is the excess reactant for the reaction below given that you start with 10.0 grams of Al and 19.0 grams of O2?
Reaction: 4Al + 3O2 ? 2Al2O3

A) Al
B) O2
C) Al2O3
D) both Al and O2
E) not enough information

Answer: B

What is the limiting reactant for the reaction below given that you start with 10.0 grams of Al and 19.0 grams of O2? Reaction: 4Al + 3O2 ? 2Al2O3

What is the limiting reactant for the reaction below given that you start with 10.0 grams of Al and 19.0 grams of O2?
Reaction: 4Al + 3O2 ? 2Al2O3

A) Al
B) O2
C) Al2O3
D) both Al and O2
E) not enough information

Answer: A

What is the limiting reactant for the reaction below given that you start with 2.50 grams C and 2.50 grams SiO2? Reaction: C + SiO2 ? SiC + O2

What is the limiting reactant for the reaction below given that you start with 2.50 grams C and 2.50 grams SiO2?
Reaction: C + SiO2 ? SiC + O2

A) C
B) SiO2
C) SiC
D) O2
E) There is no limiting reactant.

Answer: B

In order to determine the limiting reactant in a particular reaction, one must know each of the following EXCEPT:

A) the mass of each reactant present.
B) the molar mass of each reactant present.
C) the coefficient of each reactant in a balanced equation.
D) the mass of each product formed.

Answer: D

How many grams of water are theoretically produced for the following reaction given we have 2.6 moles of HCl and 1.4 moles of Ca(OH)2? Reaction: 2HCl + Ca(OH)2 ? 2H2O + CaCl2

How many grams of water are theoretically produced for the following reaction given we have 2.6 moles of HCl and 1.4 moles of Ca(OH)2?
Reaction: 2HCl + Ca(OH)2 ? 2H2O + CaCl2

A) 25.2
B) 50.4
C) 46.8
D) 103.6
E) not enough information

Answer: C

How many moles of calcium chloride are theoretically produced for the following reaction given we have 2.6 moles of HCl and 1.4 moles of Ca(OH)2? Reaction: 2HCl + Ca(OH)2 ? 2H2O + CaCl2

How many moles of calcium chloride are theoretically produced for the following reaction given we have 2.6 moles of HCl and 1.4 moles of Ca(OH)2?
Reaction: 2HCl + Ca(OH)2 ? 2H2O + CaCl2

A) 0.7
B) 1.0
C) 1.4
D) 1.3
E) not enough information

Answer: D

What is the excess reactant for the following reaction given we have 2.6 moles of HCl and 1.4 moles of Ca(OH)2? Reaction: 2HCl + Ca(OH)2 ? 2H2O + CaCl2

What is the excess reactant for the following reaction given we have 2.6 moles of HCl and 1.4 moles of Ca(OH)2?
Reaction: 2HCl + Ca(OH)2 ? 2H2O + CaCl2

A) Ca(OH)2
B) HCl
C) H2O
D) CaCl2
E) not enough information

Answer: A

What is the limiting reactant for the following reaction given we have 2.6 moles of HCl and 1.4 moles of Ca(OH)2? Reaction: 2HCl + Ca(OH)2 ? 2H2O + CaCl2

What is the limiting reactant for the following reaction given we have 2.6 moles of HCl and 1.4 moles of Ca(OH)2?
Reaction: 2HCl + Ca(OH)2 ? 2H2O + CaCl2

A) Ca(OH)2
B) HCl
C) H2O
D) CaCl2
E) not enough information

Answer: B

How many grams of NO2 are theoretically produced if we start with 1.20 moles of S and 9.90 moles of HNO3? Reaction: S + 6HNO3 ? H2SO4 + 6NO2 + 2H2O

How many grams of NO2 are theoretically produced if we start with 1.20 moles of S and 9.90 moles of HNO3?
Reaction: S + 6HNO3 ? H2SO4 + 6NO2 + 2H2O

A) 7.20
B) 331
C) 455
D) 786
E) not enough information

Answer: B

How many grams of calcium phosphate are theoretically produced if we start with 3.40 moles of Ca(NO3)2 and 2.40 moles of Li3PO4? Reaction: 3Ca(NO3)2 + 2Li3PO4 ? 6LiNO3 + Ca3(PO4)2

How many grams of calcium phosphate are theoretically produced if we start with 3.40 moles of Ca(NO3)2 and 2.40 moles of Li3PO4?
Reaction: 3Ca(NO3)2 + 2Li3PO4 ? 6LiNO3 + Ca3(PO4)2

A) 310
B) 248
C) 1054
D) 351
E) not enough information

Answer: D

How many moles of lithium nitrate are theoretically produced if we start with 3.4 moles of Ca(NO3)2 and 2.4 moles of Li3PO4? Reaction: 3Ca(NO3)2 + 2Li3PO4 ? 6LiNO3 + Ca3(PO4)2

How many moles of lithium nitrate are theoretically produced if we start with 3.4 moles of Ca(NO3)2 and 2.4 moles of Li3PO4?
Reaction: 3Ca(NO3)2 + 2Li3PO4 ? 6LiNO3 + Ca3(PO4)2

A) 7.2
B) 6.8
C) 1.2
D) 1.1
E) not enough information

Answer: B

What is the excess reactant for the following reaction given we have 3.4 moles of Ca(NO3)2 and 2.4 moles of Li3PO4? Reaction: 3Ca(NO3)2 + 2Li3PO4 ? 6LiNO3 + Ca3(PO4)2

What is the excess reactant for the following reaction given we have 3.4 moles of Ca(NO3)2 and 2.4 moles of Li3PO4?
Reaction: 3Ca(NO3)2 + 2Li3PO4 ? 6LiNO3 + Ca3(PO4)2

A) Ca(NO3)2
B) Li3PO4
C) LiNO3
D) Ca3(PO4)2
E) not enough information

Answer: B

What is the limiting reactant for the following reaction given we have 3.4 moles of Ca(NO3)2 and 2.4 moles of Li3PO4? Reaction: 3Ca(NO3)2 + 2Li3PO4 ? 6LiNO3 + Ca3(PO4)2

What is the limiting reactant for the following reaction given we have 3.4 moles of Ca(NO3)2 and 2.4 moles of Li3PO4?
Reaction: 3Ca(NO3)2 + 2Li3PO4 ? 6LiNO3 + Ca3(PO4)2

A) Ca(NO3)2
B) Li3PO4
C) LiNO3
D) Ca3(PO4)2
E) not enough information

Answer: A

What is the theoretical yield of a reaction if 25.0 grams of product were actually produced from a reaction that has a 88% yield?

A) 28.4
B) 22.0
C) 3.52
D) 352
E) none of the above

Answer: A

The theoretical yield of a reaction is 75.0 grams of product and the actual yield is 42.0g. What is the percent yield?

A) 75.0
B) 56.0
C) 31.5
D) 178
E) none of the above

Answer: B

If the theoretical yield of a reaction is 42.0 grams of product and the percent yield is 75%. How many grams were actually produced?

A) 5400
B) 56
C) 32
D) 1.8
E) none of the above

Answer: C

A balanced chemical equation used to prepare ammonium carbonate, (NH4)2CO3 , is: 2 NH3 + CO2 + H2O > (NH4)2CO3 Which choice of reactant quantities shown below would result in the greatest amount of ammonium carbonate being formed?

A balanced chemical equation used to prepare ammonium carbonate, (NH4)2CO3 , is: 2 NH3 + CO2 + H2O > (NH4)2CO3
Which choice of reactant quantities shown below would result in the greatest amount of ammonium carbonate being formed?

A) React 2 moles NH3 , 1 mole CO2 , and 1 mole H2O
B) React 2 moles NH3 , 8 moles CO2 , and 8 moles H2O
C) React 4 moles NH3 , 1 mole CO2 , and 2 moles H2O
D) React 4 moles NH3 , 2 moles CO2 , and 2 moles H2O
E) none of the above

Answer: D

Given the balanced equation CO2 + Si ? SiO2 + C, if you were to react 1 mole of CO2 with 1 mole of Si, which statement is TRUE?

A) The CO2 is the limiting reactant.
B) The Si is the limiting reactant.
C) The SiO2 is the limiting reactant.
D) You have equal stoichiometric amounts of reactants.
E) none of the above

Answer: D

Determine the theoretical yield of C when 3 units of A and 10 units of B are reacted in the following generic chemical equation: 2A + 5B ? 4C.

A) 3
B) 4
C) 6
D) 8
E) none of the above

Answer: C

Consider the following generic chemical equation: 2W + 3X ? 3Y + Z When 5 units of W and 6 units of X are allowed to react, the limiting reactant would be:

Consider the following generic chemical equation: 2W + 3X ? 3Y + Z
When 5 units of W and 6 units of X are allowed to react, the limiting reactant would be:

A) W
B) X
C) Y
D) Z
E) There is no limiting reactant in this situation.

Answer: B

Consider the following generic chemical equation: 2A + 5B ? C + 3D If you react 4 units of A with 10 units of B, which statement is TRUE?

Consider the following generic chemical equation: 2A + 5B ? C + 3D
If you react 4 units of A with 10 units of B, which statement is TRUE?

A) Substance A will be the limiting reactant.
B) Substance B will be the limiting reactant.
C) There is just enough of A and B so that everything reacts completely.
D) Substance C cannot be formed from this reaction.
E) none of the above

Answer: C

What is the theoretical yield of waffles if you have 6 cups of flour, 9 eggs and 2 tbs of oil? Given: 2 cups flour + 3 eggs + 1 tbs oil ? 4 waffles

What is the theoretical yield of waffles if you have 6 cups of flour, 9 eggs and 2 tbs of oil?
Given: 2 cups flour + 3 eggs + 1 tbs oil ? 4 waffles

A) 10
B) 12
C) 8
D) 4
E) not enough information

Answer: C

A tricycle factory uses the following items to produce one tricycle: 3 tires, 1 frame, and 2 pedals. If the factory has available 270 tires, 90 frames, and 170 pedals, which item would limit the amount of complete tricycles that can be assembled?

A) tires
B) frames
C) pedals
D) both tires and frames are limiting
E) not enough information

Answer: C

Which ingredient is the limiting reactant if you have 6 cups of flour, 9 eggs and 2 tbs of oil? Given: 2 cups flour + 3 eggs + 1 tbs oil ? 4 waffles

Which ingredient is the limiting reactant if you have 6 cups of flour, 9 eggs and 2 tbs of oil?
Given: 2 cups flour + 3 eggs + 1 tbs oil ? 4 waffles

A) flour
B) eggs
C) oil
D) waffles
E) not enough information

Answer: C

What is the theoretical yield of waffles if you have 5 cups of flour, 9 eggs and 3 tbs of oil? Given: 2 cups flour + 3 eggs + 1 tbs oil ? 4 waffles

What is the theoretical yield of waffles if you have 5 cups of flour, 9 eggs and 3 tbs of oil?
Given: 2 cups flour + 3 eggs + 1 tbs oil ? 4 waffles

A) 10
B) 12
C) 6
D) 4
E) not enough information

Answer: A

Which ingredient is the limiting reactant if you have 5 cups of flour, 9 eggs and 3 tbs of oil? Given: 2 cups flour + 3 eggs + 1 tbs oil ? 4 waffles

Which ingredient is the limiting reactant if you have 5 cups of flour, 9 eggs and 3 tbs of oil?
Given: 2 cups flour + 3 eggs + 1 tbs oil ? 4 waffles

A) flour
B) eggs
C) oil
D) waffles
E) not enough information

Answer: A

Which of the following statements is false?

A) The limiting reactant is completely consumed in a chemical reaction.
B) The theoretical yield is the amount of product that can be made based on the amount of limiting reagent.
C) The actual yield is the amount of product actually produced by a chemical reaction.
D) The percent yield = × 100%.
E) All of the above are true statements.

Answer: E

A chemist wishes to perform the following reaction: N2 + 3 H2 ? 2 NH3 If only 14.0 g of N2 is available, what is the minimum amount, in grams, of H2 needed to completely react with this quantity of N2?

A chemist wishes to perform the following reaction: N2 + 3 H2 ? 2 NH3
If only 14.0 g of N2 is available, what is the minimum amount, in grams, of H2 needed to completely react with this quantity of N2?

A) 1.01 g
B) 1.51 g
C) 3.03 g
D) 6.06 g
E) none of the above

Answer: C

Many metals react with halogens to give metal halides. For example, 2 Al (s) + 3 Cl2(g) ? 2 AlCl3 (s) If you begin with 13.5 g of aluminum:

Many metals react with halogens to give metal halides. For example,
2 Al (s) + 3 Cl2(g) ? 2 AlCl3 (s)
If you begin with 13.5 g of aluminum:

A) you will need 23.6 g Cl2 for complete reaction and will produce 66.7 g of AlCl3.
B) you will need 53.2 g Cl2 for complete reaction and will produce 66.7 g of AlCl3.
C) you will need 26.6 g Cl2 for complete reaction and will produce 49.0 g of AlCl3.
D) you will need 11.8 g Cl2 for complete reaction and will produce 49.0 g of AlCl3.
E) none of the above

Answer: B

Iron metal reacts with oxygen to produce iron(III) oxide. If you have 12.0 moles of iron for complete reaction, you need:

A) 9.0 moles of O2 and produce 3.0 moles of Fe2O3.
B) 12.0 moles of O2 and produce 24.0 moles of Fe2O3.
C) 9.0 moles of O2 and produce 6.0 moles of Fe2O3.
D) 4.5 moles of O2 and produce 3.0 moles of Fe2O3.
E) none of the above

Answer: C