Rates of Reaction - Sodium Thiosulphate and Hydrochloric acid

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Rates of Reaction - Sodium Thiosulphate and Hydrochloric acid In this piece of coursework, I will study how concentration affects the rate of reaction. I will do so by timing the reaction of Sodium Thiosulphate with an acid. In this coursework, I will include background knowledge, prediction, safety, results, calculations, graphs, an analysis, conclusion and an evaluation. In my evaluation I will comment on how reliable my results were and how I could have improved my coursework in any possible way. The definition of rate of reaction is ‘The speed at which a chemical reaction takes place’. The factors that affect the rate of reaction are: · Use of a catalyst · Temperature · Surface area · Concentration I will be investigating…show more content…
· Bags or any other obstructions should be removed. I have done a preliminary experiment to help me decide the range of concentrations to use and how much of a difference in concentration to leave between each one. My preliminary results also show that 5cm3 is a low enough concentration to begin with. My knowledge tells me that 5cm3 will take longer to react because there are less sodium particles that react with the acid. My experiment is time based and I will not have enough time to go lower. I took 10 concentrations in the preliminary test already, and this should show enough of a trend already, so there is no need to do an even lower concentration, as it would not help my experiment in any way. Apparatus: · 100ml conical flask · Stopwatch · Thermometer · Different size measuring cylinders(5ml, 10ml, 50ml) · Piece of paper. · Blue or black pen · Hydrochloric acid · Sodium Thiosulphate solution · Water · Beakers To keep this a fair test I have made sure that the acid used is the same amount every time. Also the size of the cross on the piece of paper is the same. The temperature is also the same because the results could be anomalous if tested in different conditions. Same beakers will not be used for different chemicals. This can cause reactions in the beakers and will lead to inaccuracies. GRAPH My results clearly show that as the concentration decreases, the time increases in the experiment. This links in with the
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