1. Chapter 19
Gas Stoichiometry

2. A chemist collects 23. 6g of an unknown gas from the air
A chemist collects 23.6g of an unknown gas from the air. It occupies a volume of 12.0 L at standard temperature and pressure. What common gas do you think the chemist has collected?

3. If an excess of chlorine gas reacts with a solution containing 20
If an excess of chlorine gas reacts with a solution containing 20.0g of potassium bromide how many cm3 of bromine gas can be produced at STP?
2KBr + Cl2 → Br2 + 2KCl

4. If an excess of chlorine gas reacts with a solution containing 20
If an excess of chlorine gas reacts with a solution containing 20.0g of potassium bromide how many cm3 of bromine gas can be produced at STP?
2KBr + Cl2 → Br2 + 2KCl
20.0g KBr

5. If an excess of chlorine gas reacts with a solution containing 20
If an excess of chlorine gas reacts with a solution containing 20.0g of potassium bromide how many cm3 of bromine gas can be produced at STP?
2KBr + Cl2 → Br2 + 2KCl
20.0g KBr
mol KBr
119g KBr

6. If an excess of chlorine gas reacts with a solution containing 20
If an excess of chlorine gas reacts with a solution containing 20.0g of potassium bromide how many cm3 of bromine gas can be produced at STP?
2KBr + Cl2 → Br2 + 2KCl
20.0g KBr
mol KBr
1 mol Br2
119g KBr
2 mol KBr

7. If an excess of chlorine gas reacts with a solution containing 20
If an excess of chlorine gas reacts with a solution containing 20.0g of potassium bromide how many cm3 of bromine gas can be produced at STP?
2KBr + Cl2 → Br2 + 2KCl
20.0g KBr
mol KBr
1 mol Br2
22.4 dm3
119g KBr
2 mol KBr
1 mol Br2

8. If an excess of chlorine gas reacts with a solution containing 20
If an excess of chlorine gas reacts with a solution containing 20.0g of potassium bromide how many cm3 of bromine gas can be produced at STP?
2KBr + Cl2 → Br2 + 2KCl
20.0g KBr
mol KBr
1 mol Br2
22.4 dm3
1000 cm3
119g KBr
2 mol KBr
1 mol Br2
1 dm3

9. If an excess of chlorine gas reacts with a solution containing 20
If an excess of chlorine gas reacts with a solution containing 20.0g of potassium bromide how many cm3 of bromine gas can be produced at STP?
2KBr + Cl2 → Br2 + 2KCl
20.0g KBr
mol KBr
1 mol Br2
22.4 dm3
1000 cm3
119g KBr
2 mol KBr
1 mol Br2
1 dm3
= 1880 cm3

10. In the reaction between aluminum and oxygen, how many grams of aluminum are needed to react with 5.00 dm3 of oxygen at STP?
4Al + 3O2 → 2Al2O3

11. In the reaction between aluminum and oxygen, how many grams of aluminum are needed to react with 5.00 dm3 of oxygen at STP?
4Al + 3O2 → 2Al2O3
5.00 dm3 O2

12. In the reaction between aluminum and oxygen, how many grams of aluminum are needed to react with 5.00 dm3 of oxygen at STP?
4Al + 3O2 → 2Al2O3
5.00 dm3 O2
mol O2
22.4 dm3

13. In the reaction between aluminum and oxygen, how many grams of aluminum are needed to react with 5.00 dm3 of oxygen at STP?
4Al + 3O2 → 2Al2O3
5.00 dm3 O2
mol O2
4 mol Al
22.4 dm3
3 mol O2

14. In the reaction between aluminum and oxygen, how many grams of aluminum are needed to react with 5.00 dm3 of oxygen at STP?
4Al + 3O2 → 2Al2O3
5.00 dm3 O2
mol O2
4 mol Al
27.0 g
22.4 dm3
3 mol O2
mol Al

15. In the reaction between aluminum and oxygen, how many grams of aluminum are needed to react with 5.00 dm3 of oxygen at STP?
4Al + 3O2 → 2Al2O3
5.00 dm3 O2
mol O2
4 mol Al
27.0 g
= 8.04 g
22.4 dm3
3 mol O2
mol Al

16. How many cm3 of chlorine gas are required to react with hydrogen gas to produce 50.0 cm3 of hydrogen chloride gas at STP?
H2 + Cl2 → 2HCl

17. H2 + Cl2 → 2HCl This is a volume – volume calculation.
How many cm3 of chlorine gas are required to react with hydrogen gas to produce 50.0 cm3 of hydrogen chloride gas at STP?
H2 + Cl2 → 2HCl
This is a volume – volume calculation.
We can use a shortcut for these type of calculations.
50.0 cm3 HCl

18. H2 + Cl2 → 2HCl This is a volume – volume calculation.
How many cm3 of chlorine gas are required to react with hydrogen gas to produce 50.0 cm3 of hydrogen chloride gas at STP?
H2 + Cl2 → 2HCl
This is a volume – volume calculation.
We can use a shortcut for these type of calculations.
1 cm3 Cl2
50.0 cm3 HCl
= 25.0 cm3
2 cm3 HCl

19. Homework Worksheet: Ideal Gas Equation (due tomorrow).
Worksheet: Gas Stoichiometry (due in two days).
Lab Summary: “Molecular Mass of a Gas” (due in two days).
Study Guide Chapter 19 (due in two days).
Gas Laws Lab (due today).