# Calculating the percentage of oxygen in the air

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• Created by: Z Shah
• Created on: 25-04-15 13:58
How do you calculate the percentage of oxygen in the air?
You must first take the oxygen out of the fixed amount of air. To do this, you must make a compound with the oxygen, to make sure it is not present in the air. Then you measure the amount of air left, and calculate the percentage using these results.
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How could you do this?
You could get two syringes connected with a tube containing copper turnings and 100 cm3 of air. You would then make a compound of copper oxide, by heating the copper and moving the air over the copper. Continue doing this for a few minutes.
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How would you take the results?
You would wait for the equipment to cool completely, as air expands when heated. Once it has completely cooled, measure the amount of air left in the tube. Take this away from what you started with and calculate the percentage.
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What is the equation for the reaction taking place?
2Cu(s)+O2(g)=2cuO(s)
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What is the word equation for the reaction taking place?
Copper + Oxygen = Copper Oxide
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## Other cards in this set

### Card 2

#### Front

How could you do this?

#### Back

You could get two syringes connected with a tube containing copper turnings and 100 cm3 of air. You would then make a compound of copper oxide, by heating the copper and moving the air over the copper. Continue doing this for a few minutes.

### Card 3

#### Front

How would you take the results?

#### Back ### Card 4

#### Front

What is the equation for the reaction taking place?

#### Back ### Card 5

#### Front

What is the word equation for the reaction taking place?

#### Back 