Chemical Tests

Question 1

Describe the test for hydrogen gas

Answer 1

Hold a burning splint at the end of a test tube full of gas, if it contains hydrogen then it burns with a loud ‘squeaky’ pop

Question 2

Describe the test for oxygen gas

Answer 2

Hold a glowing splint at the end of a test tube full of gas, if it contains oxygen then it relights the splint

Question 3

Describe the test for carbonate ions

Answer 3

Add any dilute acid to the solution and bubble through limewater. The acid reacts with the carbonate ions and bubbles are seen. If carbonate ions are present then the solution would be milky/cloudy.

Question 4

Describe the test for sulfate ions

Answer 4

Add dilute hydrochloric acid to sulfate ions, then add dilute barium chloride solution. A white precipitate is formed if sulfate ions are present.

Question 5

Describe the test for halide ions

Answer 5

Add dilute nitric acid, then add dilute silver nitrate to the solution.

Question 6

Precipitate of I-

Answer 6

Yellow precipitate

Question 7

Precipitate of Cl-

Answer 7

White precipitate

Question 8

Precipitate of Br-

Answer 8

Cream precipitate