Testing For Anions

Question 1

How to test if carbonate ions are present in a compound

Answer 1

-> add a few drops of dilute HCL
-> if carbonate ions are present then bubbles of CO2 will form

Can be further proved by bubbling it through limewater

Question 2

How to test if sulfate ions are present in a compound

Answer 2

add a few drops of dilute HCL
-> then add a few drops of barium chloride
-> if sulfate ions are present then WHITE PRECIPITATE of BaSO4 forms

Question 3

How to test for halide ions

Answer 3

Add a few drops of dilute nitric acid
-> add a few drops of silver nitrate
-> if a halide is present then a precipitate forms

Question 4

Colour of chlorine precipitate in halogen test

Answer 4

White

Question 5

Colour of bromine precipitate in halogen test

Answer 5

Cream

Question 6

Colour of iodide in halogen precipitate test

Answer 6

Yellow

Question 7

Why is HCL added in the first step in test for sulfate

Answer 7

Removes any interfering ions like carbonates so that they don’t react with barium to give a false positive

Question 8

Why is nitric acid added first to tests when testing for halide ions

Answer 8

To remove and react with any interfering ions such as carbonates or sulfate or sulfate which may end up giving a false positive