CHEM300B EVP Semester Exam ACTUAL
QUESTIONS AND CORRECT ANSWERS
The chemical nature of the solute is an important influence on vapor pressure lowering. True or
False? - CORRECT ANSWERS False
Vapor pressure lowering is best accomplished by a material that is all of the following except -
CORRECT ANSWERS slightly soluble
In order to calculate molar mass from freezing or boiling point data, we need to know all of the
following except - CORRECT ANSWERS the molar mass of the solvent
If the value for the number of ions formed is in error, then the molar mass will - CORRECT
ANSWERS depends on whether the value used is higher or lower than the real value
Once we measure the freezing point depression, the next step is to - CORRECT
ANSWERS calculate molality of the solution
As pressure above the solvent _______, the amount of dissolved gas ________. - CORRECT
ANSWERS increases, increases
Solubilities of gases are usually reported in grams/mL. True or False? - CORRECT
ANSWERS False
Gas stoichiometry calculations require all of the following except - CORRECT
ANSWERS identity of reactants
,In the combined gas law expression, V is in the numerator. True or False? - CORRECT
ANSWERS True
In combined gas law calculations - CORRECT ANSWERS temperatures can only be in
Kelvin
When NaCl is added to water, all of the follow occur except - CORRECT ANSWERS ions
precipitate
The solubility of gases - CORRECT ANSWERS decreases as temperature increases
At room temperature, the average kinetic energy of ice is the same as the average kinetic energy
of steam. True or False? - CORRECT ANSWERS True
One of the following statements about liquids is false - CORRECT ANSWERS liquids can
be compressed
A greater surface area decreases the amount of material dissolved. True or False? - CORRECT
ANSWERS False
Temperature affects all of the following parameters except - CORRECT
ANSWERS change in molecular configuration
Molality is defined as moles of solute divided by - CORRECT ANSWERS kg solvent
The choice of solvent has no effect on the value for the molality of a solution. True or False? -
CORRECT ANSWERS True
, The solvent with the highest freezing point depression constant is - CORRECT
ANSWERS camphor
Calculate the boiling point of the solution of 125 g KBr in 450 g water. - CORRECT
ANSWERS 450 g water = 0.45 kg
KBr molar mass = 119 g/mol
125 g / 119 g/mol = 1.05 mol
1.05 mol/0.45 kg = 2.3 m
i=2
2 × 0.512^∘C/m × 2.3 m = 2.4^∘C
To find boiling point I need to add it to 100^∘C so the final answer is 102.4 degrees C.
One of the following is not true about melting point of a solid - CORRECT
ANSWERS ionic bonds contribute to low melting points
A plot of data for Gay-Lussac's Law give a straight line. True or False? - CORRECT
ANSWERS True
QUESTIONS AND CORRECT ANSWERS
The chemical nature of the solute is an important influence on vapor pressure lowering. True or
False? - CORRECT ANSWERS False
Vapor pressure lowering is best accomplished by a material that is all of the following except -
CORRECT ANSWERS slightly soluble
In order to calculate molar mass from freezing or boiling point data, we need to know all of the
following except - CORRECT ANSWERS the molar mass of the solvent
If the value for the number of ions formed is in error, then the molar mass will - CORRECT
ANSWERS depends on whether the value used is higher or lower than the real value
Once we measure the freezing point depression, the next step is to - CORRECT
ANSWERS calculate molality of the solution
As pressure above the solvent _______, the amount of dissolved gas ________. - CORRECT
ANSWERS increases, increases
Solubilities of gases are usually reported in grams/mL. True or False? - CORRECT
ANSWERS False
Gas stoichiometry calculations require all of the following except - CORRECT
ANSWERS identity of reactants
,In the combined gas law expression, V is in the numerator. True or False? - CORRECT
ANSWERS True
In combined gas law calculations - CORRECT ANSWERS temperatures can only be in
Kelvin
When NaCl is added to water, all of the follow occur except - CORRECT ANSWERS ions
precipitate
The solubility of gases - CORRECT ANSWERS decreases as temperature increases
At room temperature, the average kinetic energy of ice is the same as the average kinetic energy
of steam. True or False? - CORRECT ANSWERS True
One of the following statements about liquids is false - CORRECT ANSWERS liquids can
be compressed
A greater surface area decreases the amount of material dissolved. True or False? - CORRECT
ANSWERS False
Temperature affects all of the following parameters except - CORRECT
ANSWERS change in molecular configuration
Molality is defined as moles of solute divided by - CORRECT ANSWERS kg solvent
The choice of solvent has no effect on the value for the molality of a solution. True or False? -
CORRECT ANSWERS True
, The solvent with the highest freezing point depression constant is - CORRECT
ANSWERS camphor
Calculate the boiling point of the solution of 125 g KBr in 450 g water. - CORRECT
ANSWERS 450 g water = 0.45 kg
KBr molar mass = 119 g/mol
125 g / 119 g/mol = 1.05 mol
1.05 mol/0.45 kg = 2.3 m
i=2
2 × 0.512^∘C/m × 2.3 m = 2.4^∘C
To find boiling point I need to add it to 100^∘C so the final answer is 102.4 degrees C.
One of the following is not true about melting point of a solid - CORRECT
ANSWERS ionic bonds contribute to low melting points
A plot of data for Gay-Lussac's Law give a straight line. True or False? - CORRECT
ANSWERS True
