CHEMISTRY 162 EXAM #1
QUESTIONS AND ANSWERS
Consider the reaction: 2N2O(g) O2(g) + 2N2(g). Which of the following will cause a shift
in the equilibrium to the right?
1. Add more N2O
2. Remove O2
3. Remove N2 - Correct Answers -All 1,2,3
500mL of a gas having pressure of 700mmHg will have a volume of ________ when it's
pressure is 1.1atm. - Correct Answers -420 ml
The solid state is defined as having no definite shape or volume - Correct Answers -
False
Some elements are more reactive than others - Correct Answers -True
You need to prepare 2.00 L of 0.100 M Na2CO3 solution. The best procedure is to
weigh out - Correct Answers -21.2 g Na2CO3 and add water until the final solution has
a volume of 2.00 L.
Increasing the pressure of a gas above a liquid, increases its solublity in the liquid -
Correct Answers -True
A 1.0g block of CaCO3 will react faster with HCl(aq) than 1.0g powdered CaCO3 -
Correct Answers -False
What is the mass percent of an ammonium carbonate solution prepared by dissolving
33.2 g of solid into 39.5 g of water? - Correct Answers -45.7%
How many grams of LiF would be present in 575 mL of 0.750 M LiF solution? - Correct
Answers -11.2
O2 gas at 25oC has pressure of 1.1 atm has density of: - Correct Answers -1.4 g/L
Calculate the molar mass of a gas that effuses at a rate 0.85 times O2 - Correct
Answers -44
, liquids have definite volume but no definite shape - Correct Answers -True
Calculate the molar mass of a gas that effuses at a rate 0.633 times O2 - Correct
Answers -80
Why does the rate of the reaction decrease over time? - Correct Answers -As the
reaction proceeds, a decrease in the concentration of reactants results in fewer
successful collisions.
What is the molar mass of a gas that has a density of 0.179 g/L at STP? - Correct
Answers -4
A 1.0M NaOH solution has Normality of: - Correct Answers -2.0
The density of C3H8 gas at STP is: - Correct Answers -1.96 g/L
500mL of a gas at 25.0oC will have a volume of 1.20L at: - Correct Answers -424
Celsius
How many calories does it take to vaporize 50.0g of benzene at its boiling point? use
table 44.2 Voyce text - Correct Answers -4720
For the reaction: H3PO4 + NaOH → H2O + Na2HPO4 (balanced?) calculate the
equivalent weight of H3PO4. - Correct Answers -49
The numerical value for the gas constant in mmHg, liters, Kelvins, and moles is: -
Correct Answers -62.36
Two liquids , A and B, are placed in two separate closed containers. When the vapor
and liquid have established equilibrium in the containers, the vapor pressure of A is
higher than that of B. - Correct Answers -A is more volatile than B
A 3.76 g sample of a noble gas is stored in a 2.00 L vessel at 874 torr and 25°C. What
is the noble gas? - Correct Answers -Ar
What is the molar mass of 3.93 g of a gas that occupies 2.00L at STP? - Correct
Answers -44
The solubility of a substance in 100.0g water is 15.0g at 25oC. 20.0g of the substance is
dissolve in 100.0g of water at 50oC and then cooled to 25oC. If no crystals appear, the
solution at 25oC is now: - Correct Answers -Supersaturated
A sample of Argon gas has a volume of 735mL at a pressure of 1.20 atm and
temperature of 300K. What is the pressure of the gas if its volume and temperature is
changed to 900mL and 200K? - Correct Answers -0.653
QUESTIONS AND ANSWERS
Consider the reaction: 2N2O(g) O2(g) + 2N2(g). Which of the following will cause a shift
in the equilibrium to the right?
1. Add more N2O
2. Remove O2
3. Remove N2 - Correct Answers -All 1,2,3
500mL of a gas having pressure of 700mmHg will have a volume of ________ when it's
pressure is 1.1atm. - Correct Answers -420 ml
The solid state is defined as having no definite shape or volume - Correct Answers -
False
Some elements are more reactive than others - Correct Answers -True
You need to prepare 2.00 L of 0.100 M Na2CO3 solution. The best procedure is to
weigh out - Correct Answers -21.2 g Na2CO3 and add water until the final solution has
a volume of 2.00 L.
Increasing the pressure of a gas above a liquid, increases its solublity in the liquid -
Correct Answers -True
A 1.0g block of CaCO3 will react faster with HCl(aq) than 1.0g powdered CaCO3 -
Correct Answers -False
What is the mass percent of an ammonium carbonate solution prepared by dissolving
33.2 g of solid into 39.5 g of water? - Correct Answers -45.7%
How many grams of LiF would be present in 575 mL of 0.750 M LiF solution? - Correct
Answers -11.2
O2 gas at 25oC has pressure of 1.1 atm has density of: - Correct Answers -1.4 g/L
Calculate the molar mass of a gas that effuses at a rate 0.85 times O2 - Correct
Answers -44
, liquids have definite volume but no definite shape - Correct Answers -True
Calculate the molar mass of a gas that effuses at a rate 0.633 times O2 - Correct
Answers -80
Why does the rate of the reaction decrease over time? - Correct Answers -As the
reaction proceeds, a decrease in the concentration of reactants results in fewer
successful collisions.
What is the molar mass of a gas that has a density of 0.179 g/L at STP? - Correct
Answers -4
A 1.0M NaOH solution has Normality of: - Correct Answers -2.0
The density of C3H8 gas at STP is: - Correct Answers -1.96 g/L
500mL of a gas at 25.0oC will have a volume of 1.20L at: - Correct Answers -424
Celsius
How many calories does it take to vaporize 50.0g of benzene at its boiling point? use
table 44.2 Voyce text - Correct Answers -4720
For the reaction: H3PO4 + NaOH → H2O + Na2HPO4 (balanced?) calculate the
equivalent weight of H3PO4. - Correct Answers -49
The numerical value for the gas constant in mmHg, liters, Kelvins, and moles is: -
Correct Answers -62.36
Two liquids , A and B, are placed in two separate closed containers. When the vapor
and liquid have established equilibrium in the containers, the vapor pressure of A is
higher than that of B. - Correct Answers -A is more volatile than B
A 3.76 g sample of a noble gas is stored in a 2.00 L vessel at 874 torr and 25°C. What
is the noble gas? - Correct Answers -Ar
What is the molar mass of 3.93 g of a gas that occupies 2.00L at STP? - Correct
Answers -44
The solubility of a substance in 100.0g water is 15.0g at 25oC. 20.0g of the substance is
dissolve in 100.0g of water at 50oC and then cooled to 25oC. If no crystals appear, the
solution at 25oC is now: - Correct Answers -Supersaturated
A sample of Argon gas has a volume of 735mL at a pressure of 1.20 atm and
temperature of 300K. What is the pressure of the gas if its volume and temperature is
changed to 900mL and 200K? - Correct Answers -0.653
