Name: ____________________________________________________Date:________________Period:__________
Gases and IMFs
1. At 47.0oC and 16.0 atmospheres, the molar volume of NH3(g) is approximately 10% less than that
predicted by the Ideal Gas Law. The actual volume of ammonia gas is smaller than the Ideal Gas Law
volume at 47.0oC and 16.0 atmospheres because they:
a. Do not move randomly
b. Decompose into the elements N2 and H2
c. Move more slowly than predicted at 47.0oC and 16.0 atmospheres
d. They do not have attractive forces or repulsive forces
e. Occupy a significant fraction of the volume of the container
2. Which gas sample has the lowest average velocity at 298K?
a. CH4 at 0.20 atm b. Ne at 0.80 atm c. He at 0.60 atm
d. CO2 at 0.40 atm
e. NO at 1.0 atm
3. A different rigid 5.00 L cylinder contains 0.176 mol of NO(g) at 298K. A 0.176 mol sample of O2(g) is
added to the cylinder, where a reaction occurs to produce NO2(g).
(d) Write the balanced equation for the reaction
(e) Calculate the total pressure, in atm, in the cylinder at 298K after the reaction is complete
4.
Which is a postulate of the kinetic molecular theory?
a. Gas molecules travel at or near the speed of light
b. The absolute temperature of a substance is proportional to the average kinetic energy of its
molecules
c. The collisions between gas molecules are inelastic
d. The energy of gas molecules is determined by quantum mechanics
e. The molecules of a sample of gas have very small volume
5. A rescue balloon filled with 10.0 L of helium is placed in a chamber. The pressure in the chamber is
reduced to 80% of atmospheric pressure, and the temperature is reduced as well. The volume of the
balloon does not change. If the original temperature is 27oC, to what temperature must have the
temperature have been lowered to achieve this effect?
a. -33oC
b. 0oC
c. 5.4oC
d. 21.6oC
e. 27K
6. At standard conditions, the ideal gas law is remarkably successful in relating the quantity of gas and its
pressure, volume, and temperature.
(a) Under what conditions of temperature will a gas deviate most from ideal behavior? Why?
(b) At what relative pressure will a gas behave in a most ideal fashion? Why?
(c) What is assumed about the size of an ideal gas molecule?
(d) How do ideal gases interact when they collide?
7. A mixture of three gases consists of a number of moles of fluorine and an equal number of moles of Xe
and H2, each of which is double the moles of F2. The total pressure of the mixture is 1000.0 torr. What
is the partial pressure of the fluorine gas?
a. 100.0 torr b. 200.0 torr c. 250.0 torr d. 333.3 torr e.400.0 torr
8. For which of the following changes is it unclear whether the volume of a particular sample of an ideal
gas will increase or decrease?
a. Increase the temperature, and increase the pressure
b. Increase the temperature, and decrease the pressure
c. Increase the temperature, and keep the pressure constant
d. Keep temperature constant, and decrease the pressure
e. Decrease the temperature, and increase the pressure
9. A rigid 5.00 L cylinder contains 24.5g of N2(g) and 28.0g of O2(g).
(a) Calculate the total pressure, in atm, of the gas mixture in the cylinder at 298 K
(b) The temperature of the gas mixture in the cylinder is decreased to 280 K. Calculate each of the
following.
(i) The mole fraction of N2(g) in the cylinder
(ii) The partial pressure, in atm, of N2(g) in the cylinder
(c) If the cylinder develops a pinhold-sized leak and some of the gaseous mixture escapes, would the
ratio moles of N2/moles of O2 in the cylinder increase, decrease, or remain the same? Justify your
answer.
10. In a recycling plant, aluminum cans are heated to the melting point of aluminum, which is 660.37oC.
The temperature is measured again when half of the aluminum is melted. What is the temperature at this
point?
a. less than 660.37oC
d. The temperature depends on the pressure
o
b. 660.37 C
e. The temperature of the liquid is greater than the temperature of
c. greater than 660.37oC
the solid
11. Which can be used to predict the strength of the intermolecular attractions between molecules?
I. The pressure of the liquid
III. The boiling point of a liquid
II. The viscosity of a liquid
IV. The mass of a liquid
a. I only
b. I and IV only
c. II and III only
d. I, II, and III only
e. II, III, and IV only
12. A different rigid 5.00 L cylinder contains 0.176 mol of NO(g) at 298K. A 0.176 mol sample of O2(g) is
added to the cylinder, where a reaction occurs to produce NO2(g).
(d) Write the balanced equation for the reaction
(e) Calculate the total pressure, in atm, in the cylinder at 298K after the reaction is complete