Gas Tests

• The test for oxygen gas is to place a glowing splint into the test tube and if the flame reignites, oxygen is present.
• If hydrogen is present, when placing a lighted splint into the test tube, the flame would extinguish with a pop sound.
• The test for carbon dioxide is to pass the gas on into limewater and if white precipitate is formed, carbon dioxide is present.
• • The test for ammonia is to hold damp red litmus paper to the test tube. If ammonia is present, the paper will turn blue.
• • If a piece of damp blue litmus paper is held to chlorine gas, the paper would turn red, before turning white.
• • In order to test for sulfur dioxide, dip a piece of filter paper in acidified purple potassium manganate, and hold the filter paper to the mouth of the test tube. If the potassium manganate turns colourless, sulfur dioxide is present.