The Effect of Temperature on Reaction Time

The Effect of Temperature on Reaction Time

Investigation

I was given the task too investigate how the temperature (heat) can

effect the reaction time of two chemicals. The two chemicals that I am

going to use throughout my investigation are:

Ÿ Sodium Thiosulphate Solution which are colourless crystals.

Ÿ Hydrochloric Acid which is a colourless substance.

Sodium Thiosulphate + Hydrochloric Acid

Na2S2O3 +2HCl

The only part of my investigation that I shall change during this

experiment is the temperature. Everything else that I shall be doing

during the investigation shall be kept exactly the same. Things such

as:

Ÿ The units of time that it takes for two chemicals to react and form

a compound.

Ÿ The units of measurement that I shall use to pour out the chemicals,

cm3 or g/l (grams per litre).

Ÿ I shall use the same amount of chemicals during each experiment, to

make it a fair test.

In order for my findings to be valid the experiment must be a fair

one. I will use the same standard each time for judging when the X has

disappeared. I will make sure that the measuring cylinders for the

Hydrochloric Acid and Thiosulphate will not be mixed up. The amount of

Hydrochloric Acid will be 15 cm3 each time, and the amount of

Thiosulphate will be fixed at 20 cm3. During the heating stage of the

experiment, a water bath will be used to heat up the acid and

thiosulphate to the necessary temperature (the water bath will be

heated up in units of 5/oC, as this is known to be the most effective

and accurate way of reaching an exact temperature.

Prediction

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

will increase. 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