Dependent: -the rate of reaction.
Controlled: - concentration of the sodium thiosulphate. - concentration of the hydrochloric acid. - the volume of the hydrochloric acid. - the volume of the sodium thiosulphate. …show more content…
This is shown in both the results table and the graph. The graph shows that the curve of best fit decreases as the temperature increases, this is because the rate of reaction is quicker and so the reaction time decreases. The results table also shows that the fastest rate was when the temperature was the hottest, this supports both the graph and the conclusion as the increase in temperature caused an increase in the rate of reaction. The results recorded do support the hypothesis. The hypothesis suggested that when the temperature of the sodium thiosulphate increased, the rate of reaction would also increase, and this is supported in the …show more content…
“Particles can only react when they collide. If you heat a substance, the particles move faster and so collide more frequently.” (http://www.chemguide.co.uk/, 2013), therefore showing the rate of reaction increases as the temperature increases. When the sodium thiosulphate temperature was 15°C, the average rate of reaction was 399 seconds, this was the slowest reaction rate as the particles weren’t colliding very quickly so the reaction took longer. When the sodium thiosulphate was 18°C it was still quite a slow reaction because the particles weren’t moving around as much, this is why the rate of reaction was 352 seconds. However, when the temperature was heated to 40°C, the particles in the sodium thiosulphate were moving faster and when they were mixed with the hydrochloric acid, the two reacted quickly because the particles were moving more, this shows why the rate of reaction at 40°C was only 106