3.10: Describe Effects of Changes in Surface Area of a Solid, Concentration of a Solution, Pressure of a Gas, Temperature and the Use of a Catalyst on the Rate of a Reaction

EFFECT OF FACTORS ON THE RATE OF REACTION

s

*SURFACE AREA OF SOLID:

s

SURFACE AREA OF SOLID

Graph showing the Effect of Surface Area on the Rate of Reaction

EXPLANATION: Compared to the reaction using lumps of reactant, the graph for the reaction using powdered reactant has a steeper gradient at the start, and plateaus faster This shows that as the surface area of a solid increases, the rate of reaction will increase (positive correlation)

s
s*CONCENTRATION OF A SOLUTION:
s

CONCENTRATION OF A SOLUTION

Graph showing the Effect of Concentration on Rate of Reaction

EXPLANATION: Compared to the reaction with low concentration of reactant, the graph with high concentration of reactant has a steeper gradient at the start, and plateaus faster This shows that as the concentration of a solution increases, the rate of reaction will increase (positive correlation)

s
s*PRESSURE OF A GAS:
s

PRESSURE OF A GAS

Graph showing the Effect of Pressure on the Rate of Reaction

EXPLANATION: Compared to the reaction using gas at low pressure, the graph of reaction using gas at high pressure has a steeper gradient at the start, and plateaus faster This shows that as the pressure of gas increases, the rate of reaction will increase

s
s*TEMPERATURE:
s

TEMPERATURE

Graph showing Effect of Temperature on Rate of Reaction

EXPLANATION: Compared to the reaction at low temperature, the graph for reaction at high temperature has a steeper gradient, and plateaus faster This shows that as temperature increases, the rate of reaction will increase

s
s*USE OF A CATALYST:
s

CATALYST

Graph showing Effect of Catalyst on Rate of Reaction

EXPLANATION: The diagram shows that when a catalyst is used, the activation energy - certain amount of energy needed for reaction to proceed, is reduced as it creates an alternative pathway requiring lower activation energy (shown by dotted graph with lower maximum energy level), Allowing More Successful and Frequent Collisions This allows more frequent successful collisions to occur, increasing the rate of reaction This shows that when a catalyst is used, the rate of reaction increases