TESTS FOR ANIONS

 

⧫ Carbonate (CO32-) :

test: add dilute hydrochloric acid.

result: effervescence (fizzing), carbon dioxide gas is released ( for testing CO2 test it with                             Limewater, which will make lime water cloudy.)

                                                                         OR

test: add dilute nitric acid 

result: lime water goes cloudy.


⧫ Chloride (Cl-) :

test: Add nitric acid, then aqueous silver nitrate.

result: white precipitate of AgCl ( soluble in ammonia )


⧫ Bromide (Br-) :

test: Add nitric acid, then aqueous silver nitrate.

result: creamy precipitate of AgBr ( slightly soluble in ammonia ).


⧫ Iodide (I-)  : 

test: Add nitric acid, then aqueous silver nitrate.

result: yellow precipitate of AgI ( insoluble in excess ammonia ).


⧫ Nitrate (NO3 -) :

test: add aqueous sodium hydroxide then add aluminium.

result: Gas produced turns damp red litmus paper blue. 


⧫ Sulphate (SO42-) :

test: Add nitric acid, then add aqueous barium nitrate.

result: white precipitate of BaSO4.


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