Assertion (A): Burning of Natural gas is an endothermic process.

Reason (R): Methane gas combines with oxygen to produce carbon dioxide and water.

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

Which of the following salts do not have the water of crystallisation?

(i) Bleaching Powder

(ii) Plaster of Paris

(iii) Washing soda

(iv) Baking soda

1. (ii) and (iv)
2. (i) and (iii)
3. (ii) and (iii)
4. (i) and (iv)

The pair(s) which will show displacement reaction is/are

(i) NaCl solution and copper metal

(ii) AgNO₃ solution and copper metal

(iii) Al₂(SO₄)₃ solution and magnesium metal

(iv) ZnSO₄ solution and iron metal

1. (ii) only
2. (ii) and (iii)
3. (iii) and (iv)
4. (i) and (ii)

Assertion (A): Nitrogen is an essential element for plant growth and is taken up by plants in the form of inorganic nitrates or nitrites.

Reason (R): The soil is the nearest and richest source of raw materials like Nitrogen, Phosphorus and other minerals for the plants.

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