Question

What type of chemical reaction takes place when
i) limestone is heated?
ii) a magnesium ribbon is burnt in air?

Answer 1

Answer:i) If limestone is heated strongly, it breaks down to form calcium oxide and carbon dioxide. Calcium oxide is also called quicklime. It is yellow when hot, but white when cold.

ii) The flame provides a source of heat so that the magnesium metal atoms can overcome their activation energy. Activation energy is the minimum energy required in order for a chemical reaction to proceed. When the magnesium metal burns it reacts with oxygen found in the air to form Magnesium Oxide.

Explanation:

Answer 2

Dear Student,

◆ Answers -

1. Decomposition reaction
2. Combination reaction

● Explanation -

(i) Limestone is heated -

• When limestone is heated, it gets converted to calcium oxide and CO2.

CaCO3 + ∆ --> CaO + CO2

• As one reactant is divided into two products, it is type of decomposition reaction.

(ii) Magnesium ribbon is burnt in air -

• When magnesium ribbon is burnt in air, it reacts with O2 to form magnesium oxide.

2 Mg + O2 --> 2 MgO

• As two reactant are combined to one product, it is type of combination reaction.

Thanks dear. Hope this helps you...