Name:
Mods:
The Gaseous State
“Gastastic Practice Problems!”
1.
A submersible balloon is sent to the bottom of the ocean. On shore, the balloon had a
capacity of 162 L when it was filled at 21.0° C and standard pressure. When it reaches the
ocean floor, which is at 5.92° C, the balloon occupies 18.8 L of space. What is the pressure
on the ocean floor, in atmospheres, kPa, mm Hg, and inches Hg?
2.
A container is filled with 24.0 g of O2 and 35.0 g of N2.
a)
What is the volume of the container at STP?
b)
What is the partial pressure (in atm) of the O2 gas?
c)
What is the mole fraction of the N2 in the mixture?
3.
Sulfur hexafluoride, SF6, is an extremely dense gas. If you had a sample of SF6 in front of
you right now, at room temperature (25°C) and pressure (1 atm), what would its density be?
If the gas was held in a canister at -75°C and 1 atm of pressure, what would the density be?
4.
Sulfur-containing compounds give skunks their potent smell. One of the principal smelly
compounds in skunk spray is (E)-2-butene-1-thiol, C4H8S.
a)
What is the root-mean-square (rms) molecular speed of a gas molecule of this
compound at 25.0° C?
b)
Using the value from part a, calculate how long it would take a molecule of
C4H7S to reach your nose if you were 150 meters from your dog who was
sprayed by a skunk.
c)
What if you were a half-mile away from your dog? How long would it take a
molecule of C4H7S to reach your nose?
5.
A 24.6 mL volume of hydrochloric acid solution reacts completely with a solid sample of
magnesium carbonate, producing 183 mL of CO2 that is collected over water at 24.0° C and
738 torr total pressure. The reaction is as follows:
2 HCl (aq) + MgCO3 (s) ® CO2 (g) + H2O (l) MgCl2 (aq)
Ø What is the Molarity of the HCl solution?