Reaction between sodium thiosulphate and hydrochloric acid

Na2S2O3 + 2HCl 2NaCl + H2O + S + SO2

Ø When pouring the acid, make sure it is done above eye level. Hydrochloric acid is also an irritant, so goggles could be used.

Ø Always wash your hands after doing an experiment, especially ones with irritant.

Ø The reaction gives off Sulphur Dioxide, which is a highly acidic gas, so as soon as the reaction has finishes, it all needs to be washed down the sink with plenty of water.

Ø Two small 100cm3 beakers, for the Sodium Thiosulphate and Hydrochloric acid

Ø A small 100cm3 conical flask to mix the fluids in

Ø A small conical flask that has a capacity of 35cm3

Ø A piece of lined paper, to judge when the reaction has finished

Ø A stop-clock to determine the duration of the reaction

Ø A calculator to work out the average reaction rate

Ø A total of 280cm3 Sodium Thiosulphate

Ø A total of 80cm3 Hydrochloric acid

A pilot study was conducted to see if the reaction b

The Hydrochloric acid, water and Sodium Thiosulphate were measured into the conical flask. They were always put in the same order, so that it is a fair test. The order was Sodium Thiosulphate, water and finally Hydrochloric acid. As soon as the acid went in (therefore starting the reaction), the timer was also started. The conical flask was placed onto some lined paper, and as soon as the lines disappeared due to cloudiness of the mixture, the timer was stopped. This happened for every different concentration.

I predict that the more Sodium Thiosulphate there is, the faster the reaction will be. This is because it is a larger concentration, and so there are more particles to react; for a reaction to occur, particles have to collide with each other. Only a small percent result in a reaction. Only particles with enough energy will react after colliding. If the frequency of collisions is increased, the rate of reaction will also increase.

§ The lines on the paper could have got wet, and so would not show up as much and the timer could have been stopped before it should have been.

There are many things which could have caused wrong results or slight differences in outcome, such as;

Some topics in this essay:
Sodium Thiosulphate, Average Rate, Rate S-1, Thiosulphate Hydrochloric, NR NR, SO2 Safety, Sulphur Dioxide, Thiosulphate Vol, Vol HCl, nr nr, , sodium thiosulphate, nr nr nr, hydrochloric acid, 10 10, conical flask, Ø total, faster reaction, timer stopped, cm3 vol, 20 10 15, 10 28, 34 20 10, 15 39 37, 29 34 20,