The Effect of Sodium Thosulphate Solution on the Rate of Its Reaction with Hydrochloric Acid

The Effect of Sodium Thosulphate Solution on the Rate of Its Reaction with Hydrochloric Acid

Aim

To find out how the concentration of sodium thiosulphate solution

affects the rate of its reaction with hydrochloric acid.

Prediction

I predict that the higher the concentration of Sodium Thiosulphate

solution the faster it will react with the hydrochloric acid. Firstly

for a reaction to take place the particles must collide and secondly

collide with enough energy to break and make new bonds. When the

sodium thiosulphate is concentrated there are more particles in a

given volume, therefore there is a greater chance of the particles

successfully colliding and reacting with the hydrochloric acid. The

more collisions between particles in a given time, the faster the

reaction will take place.

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Word Equation

[IMAGE]Sodium Thiosulphate Sodium Chloride + Sulphur dioxide

+ Hydrochloric Acid + Sulphur + Water

Symbol Equation

[IMAGE]Na₂S₂O₃ + 2HCl 2NaCl + SO₂ + S + H₂O

The products of this equation are sodium chloride, commonly known as

salt, sulphur dioxide, which is a highly toxic gas, water and sulphur.

The sulphur is a precipitate and this is what turns the solution

cloudy.

Method

To find a suitable method I firstly looked back at the previous work I

had done in class, to see if there were any similar experiments that

could be used as pilot tests. I found that I had done a similar

experiment using the same reactants, but instead of looking at the

effects of concentration, I had looked at temperature. The amounts

used 50cm³ Sodium Thiosulphate and 5cm³ Hydrochloric acid. The

experiment had worked well and I had drawn good results so these

amounts were suitable. Also I looked in a chemistry book by Hunt and

Sykes book which happened to have the same experiment in. They to had

used these amounts and this confirmed the quantities that I thought

would be appropriate to use, although I decided to go up in fives