Rate of Reaction Investigation

Rate of Reaction Investigation

Aim

To investigate how changing the concentration of a reactant (sodium

thiosulphate) affects the rate of reaction, and why.

Prediction

I predict that increasing the concentration of the reactant will

increase the rate of reaction. This is because as the concentration of

the solution increases, the numbers of particles present increases, in

the same volume. This means the particles are closer together and

there is a greater possibility of a collision and reaction.

I also predict that when the concentration of sodium thiosulphate is

doubled than the rate will also be doubled, so when the volume of

sodium thiosulphate is 40ml the rate will be twice as much as when the

volume was 20ml.

Apparatus list Diagram

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· 1 conical flask

· 2 beakers (200ml)

· 1 large measuring cylinder (100ml)

· Piece of lined paper

· Water

· Sodium thiosulphate (Na S 0 )

· Hydrochloric acid

· Timer

· 1 small measuring cylinder (10ml)

Method

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1. Take two 200ml beakers, fill one with hydrochloric acid and the

other with sodium thiosulphate, and label both beakers.

2. Measure 90ml sodium thiosulphate into a 100ml measuring cylinder.

3. Using the same measuring cylinder with sodium thiosulphate still

in, fill solution up to 100ml with water.

4. Pour solution into conical flask and place conical flask on top of

lined paper.

5. Measure out 10ml of hydrochloric acid into 10ml measuring cylinder.

6. Pour hydrochloric acid, from 10ml measuring cylinder, into the

conical flask containing sodium thiosulphate and water. Begin timing

as soon as this is added the mixture should go cloudy, wait until the

lines on the paper are no longer visible through the mixture and stop

the timer.

7. Record result for 90ml sodium thiosulphate and 10ml water in table.

8. Wash out conical flask and 100ml measuring cylinder.

9. The range of results in this experiment goes from 100ml sodium