The Effect of Temperature on the Rate of Reaction

The Effect of Temperature on the Rate of Reaction

Plan

We must produce a piece of coursework investigating the rates of

reaction, and the effect different changes have on them. The rate of

reaction is the rate of loss of a reactant or the rate of formation of

a product during a chemical reaction. There are five factors which

affect the rate of a reaction, according to the collision theory of

reacting particles: temperature, concentration (of solution), pressure

(in gases), surface are (of solid reactants), and catalysts.

I will investigate the effect temperature has on a reaction.

Aim

To investigate how a change in temperature effects the rate of a

chemical reaction.

The reaction that will be used is:

Sodium Thiosulphate + Hydrochloric Acid --> Na2S2O3(aq)+ 2HCl(aq)

Sodium Chloride + Water + Sulphur Dioxide + 2NaCl (aq)+ H2O(l)+ SO2

(g)+ Sulphur-S (s)

Prediction

I predict that as the temperature is increased the rate of reaction

will increase. This means that the graph drawn up in my analysis will

have positive correlation, and will probably be curved as the increase

in rate of reaction will not be exactly the same as the temperature is

increased. This can be justified by relating to the collision theory.

When the temperature is increased the particles will have more energy

and thus move faster. Therefore they will collide more often and with

more energy. Particles with more energy are more likely to overcome

the activation energy barrier to reaction and thus react successfully.

If solutions of reacting particles are made more concentrated there

are more particles per unit volume. Collisions between reacting

particles are therefore more likely to occur. All this can be

understood better with full understanding of the collision theory

itself:

For a reaction to occur particles have to collide with each other.

Only a small percent result in a reaction. This is due to the energy

barrier to overcome. Only particles with enough energy to overcome the

barrier will react after colliding. The minimum energy that a particle

must have to overcome the barrier is called the activation energy. The

size of this activation energy is different for different reactions.

If the frequency of collisions is increased the rate of reaction will

increase. However the percent of successful collisions remains the

same. An increase in the frequency of collisions can be achieved by

increasing the temperature, concentration, pressure, and surface area.

Also I predict that if the temperature is doubled, then the time taken

for would be more than half because not only would the particles be

moving faster to create more collisions, but they would also have more

energy so there would be more successful collisions