# Gas Laws - Volume, Density, and Temperature

1.) The density of liquid nitrogen is 0.808 g/mL at -196 degrees Celsius. What volume of nitrogen gas at STP must be liquefied to make 10.0 L of liquid nitrogen?

2.) Calculate the volume occupied by 2.5 mol of an ideal gas at STP.

3.) A hydrocarbon (compound containing only hydrogen and carbon) was analyzed to be 85.7 mass percent carbon and 14.3 mass percent hydrogen. At 26 degrees Celsius and 745 torr pressure a sample with a volume of 1.13 L had a mass of 1.904g. Determine the molecular formula.

4.) HCl(g) can be prepared by reaction of NaCl with H2SO4. What mass of NaCl is required to prepare enough HCl to fill a 340. mL cylinder to a pressure of 151 atm at 20.0 degrees Celsius.

5.) You are not sure whether to fill a balloon with He or hot air. To what temperature would the air have to be heated for a balloon to rise to the same height as a balloon filled with He at 25.0 degrees Celsius?

6.) At 27.7mL sample CO2(g) was collected over water at 25.0 degrees celsius and 1.00 atm. What is the pressure in torr due to CO2(g)? (The vapor pressure of water at 25.0 degrees celsius is 23.8 torr.) What will the volume of CO2(g) be at the same temperature and pressure after removing the water vapor?

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1.) The density of liquid nitrogen is 0.808 g/mL at -196 degrees Celsius. What volume of nitrogen gas at STP must be liquefied to make 10.0 L of liquid nitrogen?

Solution:

10.0 L of liquid nitrogen contains:

T = 273.15 K

P = 1 atm

n = 288.57 mol

V = ?

2.) Calculate the volume occupied by 2.5 mol of an ideal gas at STP.

Solution:

n = 2.5 mol

T = 273.15 K

P = 1 atm

V = ?

3.) A hydrocarbon (compound containing only hydrogen and carbon) was analyzed to be 85.7 mass percent carbon and 14.3 mass percent hydrogen. At 26 degrees Celsius and 745 torr pressure a sample with a volume of 1.13 L had a mass of ...

#### Solution Summary

The solution uses gas laws to calculate and answer various questions on densities, volumes and temperatures of gases.