Question

a) Distinguish between the following using a chemical test
I)Sodium nitrate and ammonium nitrate
ii) Calcium sulphate and Calcium sulphite.​

Answer 1

Answer:

a)(i) Chemical test for ammonia:

If a rod dipped in concentrated hydrochloric acid is brought near ammonia gas, dense white fumes of ammonium chloride (NH4Cl) are formed.

 

(ii) Chemical test for Sulphur dioxide:

It decolorizes pink coloured potassium permanganate solution.



 

(iii) Chemical test for HCl:

When HCl gas is passed through AgNO3 solution, white precipitates of AgCl are formed which gets dissolved in excess of NH4OH.



 

(iv) Chemical test for Chlorine:

It turns moist starch iodide paper (KI + starch solution) blue black.

 

(v) Chemical test for Carbon dioxide:

When this gas is passed through lime water, it turns milky due to the formation of white precipitates of CaCO3 and on passing excess of carbon dioxide gas, this milkinessdisappears.

 

(vi) Chemical test for oxygen:

This gas is absorbed in colourless alkaline solution ofpyrogallol and turns it dark brown.

 

(vii)Chemical test for hydrogen:

It burns with a pop sound when a burning taper is brought near it.