Oxygen & Oxides

Question 1

What are gases present in air and what are their percentages?

Answer 1

Nitrogen - 78%
Oxygen - 21%
Argon - 0.93%
Carbon dioxide - 0.04%

Question 2

How can you make oxygen in the lab?

Answer 2

Hydrogen peroxide will decompose into water and oxygen. The reaction is sped up by manganese(IV) oxide catalyst

Question 3

What colour flame does magnesium burn with?

Answer 3

Bright white flame

Question 4

What colour flame does carbon burn with?

Answer 4

Orange/yellowy flame

Question 5

What colour flame does Sulfur burn with?

Answer 5

A pale blue flame

Question 6

Give one way that carbon dioxide can be produced?

Answer 6

Calcium carbonate is put at the bottom of a flask and dilute hydrochloric acid is added. The HCl and calcium carbonate react to produce calcium chloride, water and carbon dioxide. The carbon dioxide gas is collected in a gas syringe