The document discusses the standard molar volume of gases and the ideal gas law. 1) The standard molar volume of any gas is 22.4 L at 0°C and 1 atm of pressure (STP). 2) The ideal gas law equation relates the pressure (P), volume (V), amount of gas (n), temperature (T), and gas constant (R). It can be used to calculate any one variable if the others are given.

1. II. Standard Molar Volume

2. II. Standard Molar Volume
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Objectives:
1. know that the standard molar volume of a gas = 22.4 L at STP.
2. know standard temperature = 0 ˚C.
3. know that standard pressure = 1 atm.
4. calculate the volumes of samples of gases at STP.

3. II. Standard Molar Volume
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• The mole is the SI unit for amount of substance.
– The mole is used to measure amounts of solids.
– The mole is used to measure amounts of substance dissolved in liquids.
– The mole is used to measure amounts of gases.

4. II. Standard Molar Volume
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• 1 mole of any substance contains an Avogadro’s number of either atoms,
ions, or molecules.
Example 1: 1 mole He = 6.02 x 1023 He atoms
Example 2: 1 mole N2 = 6.02 x 1023 N2 molecules

5. II. Standard Molar Volume
• Equal amounts of gases, in moles, occupy the same volume under the same
temperature and pressure conditions.

6. II. Standard Molar Volume
Standard Molar Volume
• 1 mole of any gas will occupy
22.4 L of volume at STP.
• STP = standard temperature and
pressure conditions.
– T = 0 ˚C
– P = 1 atm

7. II. Standard Molar Volume
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• 1 mole of any gas will occupy the same volume at STP:
1 mole He = 22.4 L He
1 mole O2 = 22.4 L O2
1 mole N2 = 22.4 L N2
1 mole Ar = 22.4 L Ar
1 mole CO2 = 22.4 L CO2

8. II. Standard Molar Volume
• The standard molar volume equality, 1 mole (any gas) = 22.4 L (any gas), is
used as a conversion when calculating quantities of gases in chemical
changes.

9. III. The Ideal Gas Law

10. III. The Ideal Gas Law
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Objectives:
1. know the units for each quantity of the ideal gas law equation.
2. calculate the pressures, volumes, temperatures, and amounts of gases
by the ideal gas law equation.

11. III. The Ideal Gas Law
• The following must be specified to fully describe the state or condition of
any sample of gas:
1. moles of gas
2. temperature of the gas
3. pressure of the gas
4. volume of the gas

12. III. The Ideal Gas Law
• The Ideal Gas Law equation: PV = nRT
P = pressure in units of atmospheres (atm)
V = volume in units of liters (L)
n = amount of gas in moles (mol)
R = molar gas constant; R = 0.0281 L atm / mol K
T = temperature in Kelvin (K)

13. III. The Ideal Gas Law
Given: PV= nRT
Derive an equation solving for volume.

14. III. The Ideal Gas Law
Given: PV= nRT
Derive an equation solving for pressure.

15. III. The Ideal Gas Law
Given: PV= nRT
Derive an equation solving for temperature.