Question

*Give one example of each which illustrates the following characteristics of a
chemical reaction.

1. A catalytic reaction.
2. Change of colour.
3. Change in state.
4. An exothermic reaction.​

Answer 1

Explanation:

2.Change in colour:

Reaction between lead nitrate solution and potassium iodide solution. Pb(NO3)2(aq) +2KI -------> Pb12(s) + 2KNO3(aq) In this reaction colour changes from colourless to yellow.

3.Change in state:

When wax is burnt in the form of wax candle then Water and carbon dioxide are formed. Wax is a solid water is a liquid whereas carbon dioxide gas.