Factors Affecting Rate of Chemical Reaction

The rate of chemical reaction depends on 

1. Nature of reactants.
2. Concentration of reactants.
3. Effect of temperature.
4. Surface area of reactants.
5. Presence of catalyst.
6. Pressure changes in gaseous reactants.
7. Effect of light.

1. Nature of Reactant:

The rate of reaction is affected by the nature of reactants taking part in the reaction. For example, when iron, zinc, and gold react with hydrochloric acid. The reaction is slow, but with a piece of gold, there is no evidence of reaction. This is because of the position of these metals in the activity series. Gold is lower than hydrogen in the activity series, it cannot displace hydrogen from the solution of its salt.

Zn_(s) + 2HCl_(aq) →  ZnCl_2(aq) + H_2(g)

Fe_(s) + 2HCl_(aq0  → FeCl_2(aq) + H_2(g) 

Thus the rate of reaction is determined by the chemical nature of different substances.

2. Concentration of Reactants: