Concentration will effect the rate of reaction, which will lead to more reactants per volume and also more collisions which higher the rate of reaction.
During this investigation I will mix these three reactants. Sodium thiosulphate, water and hydrochloric acid increase the temperature as I go along to see if it speeds up the rate of reaction. I will time how long before a black cross-below the mixture is clouded over by the sulphur is produced.
Fair test.
The variables that I will keep the same will be amount of reactants, concentration of reactants and a cross on paper. I will repeat each temperature 3 times to get an average.
The only variable that I will change will be the temperature. I will keep the variables the same so that my results are reliable and allow me to draw a good conclusion.
Prediction.
I predict that the rate of reaction will increase as the temperature increases.
The scientific reasons behind my prediction are the hotter the temperature the more energy particles will be given which makes the reactants move faster also due to this their will be more collisions. I got this information from collision theory.
Method.
- I need to get the equipment and then set it up.
- Gather the reactants and then measure them out.
- Collect the sodium thiosulphate and water then place it onto a Bunsen burner flame then heat it to the right temperature in a conical.
- Put the conical flask on a piece of paper it with a marked cross on it.
- Add the acid then start the stop clock.
- When the cross has gone stop the clock and record the result.
- Do it again two more times to get an average.
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Repeat the procedure at 300C, 40oC, 500C and 600C.
Analysis.
I have found out that the higher the temperature the faster the rate of reaction.
The pattern that my results followed was at low temperature the slower the rate of reaction and at high temperature the faster the rate of reaction like 20oc took 87.32 and 60oc took 69.37.
All of my results followed a pattern because I done the experiment accurately.
My results followed this pattern because there was more temperature, more energy so they moved faster which means more collisions and more products. Where made in a shorter space of time. Using my results I can now believe that my prediction was correct.
Evaluation.
I think my investigation was a success because I got accurately results and they followed a pattern.
If I were to do the investigation again I would heat the acid as well as the sodium thiosulphate and water so that the temperature did not fall when cold acid was added. I would also use a pipette for measurement.
I could expand my investigation to look at what happens if I lower temperature instead of heating it up.
