On adding conc. H₂SO₄ to cane sugar, the colour observed is :

1. yellow
2. black
3. green
4. violet

The acid which produces charcoal from sugar is :

1. conc. HNO₃
2. conc. HCl
3. Conc. H₂SO₄
4. conc. H₃PO₄

The compound formed by the oxidation of sulphur by nitric acid is :

P — Sulphuric acid

Q — Nitrogen dioxide

R — Sulphur dioxide

1. Only P
2. Only Q
3. Only R
4. Both P and Q

Assertion (A): Sulphuric acid is known as the oil of vitriol.

Reason (R): Sulphuric acid was first obtained by heating crystals of green vitriol.

1. Both A and R are true and R is the correct explanation of A.
2. Both A and R are true but R is not the correct explanation of A.
3. A is true but R is false.
4. A is false but R is true.