Qualitative Analysis Anions

Question 1

CO32-

Answer 1

Add dilute HCL and pass gas produced through limewater.

Effervescence is observe and gas given off forms white precipitate with limewater. —>Gas given off is carbon dioxide

Question 2

Cl-

Answer 2

Add dilute nitric acid then silver nitrate solution

White precipitate of silver chloride is formed.

Question 3

I-

Answer 3

Add dilute nitric acid and add silver nitrate solution

Yellow precipitate of silver iodide is formed

Question 4

NO3-

Answer 4

Add dilute sodium hydroxide then add a piece of aluminium foil. Warm mixture and test gas given off with piece of moist red litmus paper

Moist red litmus turns blue —>gas given off is ammonia
No precipitate

Aluminium reacts with NaOH to form H2, which reacts with nitrate to form ammonia

Question 5

SO42-

Answer 5

Add dilute nitric acid and then add barium nitrate solution

White precipitate of barium sulfate formed