Tests For Anions

Question 1

Test for carbonates

Answer 1

Carbonate + acid —> salt + carbon dioxide + water
- add dilute hcl to sample
- run any gas produced in limewater and see if it goes cloudy white
- if carbonates were present in the sample, carbon dioxide will be produced

Question 2

Test for sulfates

Answer 2

Barium ion + sulfate ions —> barium sulfate (white precipitate)
- add dilute hcl to sample to remove any carbonate and sulfite ions
- add barium chloride solution, if sulfate ions are present a white precipitate will form

Question 3

Test for halide ions
(Chloride, bromide, iodide ions)

Answer 3

Halide ions + nitric acid —> precipitate
- add dilute nitric acid to remove carbonate and sulfite ions
- add silver nitrate and precipitate will form if halide ions are present
* chloride ions form white precipitate
* bromide ions form cream precipitate
* iodide ions form yellow precipitate