1. Molar Volume
How easy is this?

2. What is Molar Volume?
Molar Volume is the volume that one mole of a gas occupies under Standard Conditions.

3. What is STP
The standard conditions are known as STP, which stands for Standard Temperature and Pressure.
STP is defined as
Temperature= 0 degrees Celsius (0 ° C)
Pressure = 1 atmosphere (1 atm)

4. Ratio for mol to gas volume?∞
1 mol gas = 22.4 L STP

5. This is how easy Molar Volume problems are at STP
At STP, one mole of a gas is equal to 22.4 L of that gas.

6. Got it? ∞
1 mol gas = 22.4 L STP

7. Got it? ∞
1 mol gas = 22.4 L STP

8. Got it? ∞
1 mol gas = 22.4 L STP

9. Let’s check out a problem
Holey Moley has 2.31 mols of O2 in his room which is at STP. How many liters does he have?
P: 2.31 mol O2 = ? L O2
P: mol O2  L O2
2.31 mol O L O2 gas
1 mol O2 S=
2.31 mol O2 = 51.7 L O2
WOOOOO… that was too easy!!

10. Let’s check out a problem
Holey Moley has 2.31 mols of O2 in his room which is at STP. How many liters does he have?
2.31 mol O L O2 gas
1 mol O2
2.31 mol O2 = 51.7 L O2
WOOOOO… that was too easy!!

11. Mrs. Platt has 34.5 grams of ammonia. How many mL does she have at STP?
P: 34.5 g NH3 =? mL NH3 gas
P: g NH3  mol NH3  L NH3
34.5 g NH3 1 mol NH L NH3
g NH3 1 mol NH3 S:
S:34.5 g NH3 = 45.4 L NH3
Molar Mass
Molar Volume

12. You Try the Next two before you go to the answers. (Hint it’s 3 steps)

13. If I start with 456 mL of Cl2, how many grams do I have @ STP?
P: 456 mL Cl2 =? G Cl2
P: mL Cl2 L Cl2  mol Cl2 g Cl2
456 mL Cl L 1 mol Cl g Cl2
1000 mL L Cl mol Cl2 S=
456 mL Cl2= 1.44 g Cl2
Molar Volume
Molar Mass

14. A reaction requires 23. 4 grams of steam to initiate
A reaction requires 23.4 grams of steam to initiate. How many molecules of steam is this at STP? Remember that there are x 1023 molecules in 1 mole.
P: 23.4 g H2O = ? Molecules of H2O
P: grams H2O  mol H2O  molecules H2O
23.4 g H2O mol H2O x 1023 molecules H2O
18.02 g H2O 1 mol H2O
S: x 1023
S: 7.82 x 1023 molecules of H2O

15. Complete the 2 on the back, then the worksheet is homework.