Question

State how addition of – 

1. copper 

2. NaCl to hot cone. H₂SO₄ serves as a test for the latter. 

Answer 1

1. Copper turnings when heated with cone. H₂SO₄ gives a colourless suffocating gas with a smell of burning sulphur(SO₂ ). The gas turns orange coloured acidified potassium dichromate solution green. This can be used as a test for cone. H₂SO₄ .

2. Common salt (NaCl) when heated with cone. H₂SO₄ gives a colourless gas pungent smell only which (HCl) gives white fumes with NH₃ . This can be used as a test for cone. H₂SO₄ .