The Effect of Temperature on the Rate of Reaction of Sodium Thiosulphate and Nitric Acid

The Effect of Temperature on the Rate of Reaction of Sodium Thiosulphate and Nitric Acid

Planning

Aim

The aim of this investigation is to find out and observe how the

temperature affects the rate of reaction. I am going to investigate

the rate at which the solutions of nitric acid (HNO³) and sodium

thiosulphate (Na²S²O³) turn cloudy (when mixed together), when the

temperature is changed.

Variables

In this investigation I will only have one variable:

§ The temperature of both solutions (sodium thiosulphate and Nitric

acid), so that I will be able to see the affect of temperature on the

rate of reaction. The temperature will be measured in Celsius.

Fair Test

In this investigation I will keep the following constant:

Ÿ The volume of sodium thiosulphate, at 20cm³ (16gl), so that the

results will be consistent;

Ÿ The volume of nitric acid, at 5cm³, so that the results will be

consistent;

Ÿ The volume of water, at 30cm³, so that the results will be

consistent;

Ÿ The same apparatus all the time, so that human error can help to be

ruled out; and

Ÿ The same crossed paper for each test, so that a fainter or bolder

cross won’t be used. If that happened then the results won’t be

consistent.

Another way in which I will keep this a fair test is by repeating the

experiment 3 time for each temperature. I will also carry out the

experiment indoors (with the lights on at all time during the

experiment), so that the weather won’t effect the temperature of the

experiment. Not only that, after every experiment I wil have to wash

out each of the apparatus, thoroughly, so that the solutions won’t be

able to get contaminated, via the apparatus.

In order to make these results precise and reliable I will measure all

the solutions with accuracy and I will try to time the reaction as

precise as I can (by starting the time as soon as I pour the solutions