Finding oxygen percentage using Iron

Question 1

Explain:

Answer 1

To find the volume of air in the conical flask we can fill it with water and then pour out the water into a measuring cylinder

Question 2

How to do it:

Answer 2

Put wet iron fillings in a conical flask

Record initial reading of gas syringe

Leave apparatus in place for a week until the reading on the gas syringe stops changing

Record the final reading on the gas syringe