You can Investigate the Proportion of Oxygen in the Atmosphere Using Copper

Question 1

What happens when it’s heated?

Answer 1

Copper reacts with oxygen in the air to make copper(II) oxide

Question 2

What does the reaction do with the oxygen?

Answer 2

Uses it up

Question 3

What can you do if you if you heat an excess of copper in a tube and pass air over it using two syringes?

Answer 3

Use markers on the syringes to tell how much oxygen has been used up

Question 4

What is the chemical equation for the reaction?

Answer 4

2Cu + O2 —> 2CuO

Question 5

If you start with 100cm³ of air how much will you end up with once the reactions finished and the air has cooled?

Answer 5

80cm³

Question 6

What can we say if 20cm³ of air has gone?

Answer 6

Then around 20% of the air must be oxygen

Question 7

See apparatus set up page 37

Answer 7

Ok