Gas Chemistry

What is the approximate percentage of nitrogen in the Earth's atmosphere?

• 21%

• 78%

• 1%

• 0.04%

Which gas in the atmosphere is known for its strong triple covalent bond, making it unreactive?

• Oxygen

• Carbon dioxide

• Nitrogen

• Argon

What is the main use of nitrogen in food packaging?

• To add flavour

• To prevent spoilage

• To increase weight

• To add colour

What is the test for ammonia gas?

• It turns limewater milky

• It forms white smoke with concentrated hydrochloric acid

• It burns with a blue flame

• It changes litmus paper to red

Which metal is commonly used in the laboratory preparation of hydrogen gas?

• Copper

• Zinc

• Iron

• Magnesium

What is the main use of hydrogen in weather balloons?

• To provide weight

• To act as a coolant

• To lift the balloon

• To add colour

How is oxygen gas commonly prepared in the laboratory?

• By heating calcium carbonate

• By the catalytic decomposition of hydrogen peroxide

• By reacting zinc with hydrochloric acid

• By burning magnesium

What is the product when carbon reacts with oxygen?

• Carbon monoxide

• Carbon dioxide

• Carbonic acid

• Calcium carbonate

What is the main use of carbon dioxide in fizzy drinks?

• To add sweetness

• To provide carbonation

• To preserve the drink

• To add colour

What happens when carbon dioxide is bubbled through limewater?

• The solution turns blue

• The solution turns milky

• The solution turns red

• The solution remains colourless