1.1 What is Chemistry?

http://www.ck12.org Chapter 14. The Properties of Gases

FIGURE 14.10

Molecular Mass vs. Time.

Lesson Summary

• Dalton’s law of partial pressures states that the total pressure of a gas mixture is the sum of the partial pressures
  of each gas component.


• Mole fractions describe the fraction or percentage of a mixture that is made up of a particular substance.


• The rates of diffusion and effusion for a gas are inversely proportional to the square root of its molar mass.

Lesson Review Questions

1. Say you have a closed container containing 10 moles of a mixture of gases. If you removed 2 moles of one
   of the gases and replaced it with 2 moles of a lighter gas, would the total pressure in the container increase,
   decrease, or remain the same?


2. A gaseous mixture consists of 5.2 moles of helium and 2.1 moles of nitrogen. If the volume of the container
   is 11.2 L and the temperature is 273 K, calculate the following:
   
   
   1. The total moles of gas particles
   
   
   2. The mole fraction of each gas
   
   
   3. The total pressure of the mixture
   
   
   4. The partial pressure of each gas
   
   
   
   


3. A gaseous mixture consists of 11.0 g of CO 2 and 48.0 g of O 2. If the volume of the container is 2.24 L and
   the temperature is 273 K, calculate the following:
   
   
   1. The moles of each gas
   
   
   2. The total moles of gas particles
   
   
   3. The mole fraction of each gas