Manufacture, Properties, uses
When concentrated sulphuric acid was added to an unknown salt present in a test tube a brown gas (A) was evolved. This gas intensified when copper turnings were added to this test tube. On cooling, the gas (A) changed into a colourless solid (B).
1) Identify (A) and (B).
2) Write the structures of (A) and (B).
3) Why does gas (A) change to solid on cooling?