In order for reaction to take place, reacting particles need to collide in the desired orientation, with a certain minimum of energy This energy is known as activation energy.
Activation energy is the minimum energy required for the reaction to take place.
2. Factors affecting rate of reaction
- concentration of solution
- pressure of gases
- particle size of solids
Note that the catalyst remains chemically unchanged at the end of the reaction.
If a reaction gives out gases, the following setup could be used to study the rate of reaction, by obtaining the volume of gas evolved at regular time intervals..
3.1 Measuring change in mass with time, to follow rate of reaction.
|Rate of reaction experiments - measuring change in mass with time|
|Rate of reaction experiments - measuring change in volume of gas with time|
4. Interpret data obtained from experiments concerned with speed of reaction
Example. An experiment was set up to study the rate of reaction between excess powdered calcium carbonate and 20 cm3 of 0.25 mol/dm3 sulfuric acid at 35oC. The volume of carbon dioxide evolved with time is plotted on a graph below:
|Rate of reaction experiments - graph of volume of gas evolved with time|
|Effect of surface area of solids on rate of reaction|
- Quizzes and Tests on Rate of Reaction