tests

Question 1

hydrogen gas

Answer 1

place a lighted splint over the mouth of the test tube when effervescence is observed. Hydrogen gas present will extinguish the lighted splint with a ‘pop’ sound.

Question 2

carbon dioxide

Answer 2

bubble the gas into limewater (aqueous sodium hydroxide). Carbon dioxide forms a white precipitate with limewater.

Question 3

ammonia gas

Answer 3

• ammonia gas is colourless and pungent

- turns moist red litmus paper blue