1. Unit 5A Mole – Volume Relationships
ABClark-Grubb

2. Mole – Volume Relationships
The molar volume is used to convert a known number of moles of gas to the volume of the gas at STP.
STP (or standard temperature & pressure) means the temperature is 0°C and a pressure of kPa
22.4 L = 1 mol is the standard volume at STP

3. Calculating the Volume or Moles of a Gas at STP
Determine the volume, in liters, of 0.60 mol SO2 gas at STP.
0.60 mol SO2
22.4 L SO2 =
13.44 L SO2
1 mol SO2
= L SO2
rounded to the correct SIG FIGS

4. Calculating moles or volume of a Gas at STP
At STP, how many moles are in 28.0 L of helium?
28.0 L He
1 mol He =
1.25 mol He
which is in the correct SIG FIGS
22.4 L He

5. Try this… What is the volume of 3.70 g N2 at STP? = 2.96 L N2
1 mol N2
22.4 L N2
3.70 g N2 =
2.96 L N2
28.0 g N2
1 mol N2
= L N2
Rounded to the correct SIG FIGS

6. Try this … How many molecules of carbon dioxide are in 7.50L?
1 mol CO2
6.02 X 1023 molecules
7.50 L CO2
22.4 L CO2
1 mol CO2
= 2.02 X 1023 molecules CO2
Rounded to the correct SIG FIGS