There are five main factors which affect the rate of chemical reactions: temperature, concentration, pressure, surface area, presence of a catalyst.
The collision theory states that particles must collide with enough energy to change into new substances. The minimum energy they need is called the 'activation energy'. If we increase the chance of individual particles reacting, we will also increase the rate of reaction.
Breaking large pieces of a solid into smaller pieces exposes new surfaces which means there are more collisions in the same time and so a powder reacts faster than large lumps of a substance.
Catalysts increase the rate of reaction without being used up. They do this by lowering the activation energy needed. Different reactions need different catalysts. Catalysts are important in industry because they reduce costs.
Comments
Report