Effect of temperature on rate of reaction

To start the experiments fill the flask with 50cm³ of sodium thiosulphate into the large beaker. Fill the large beaker up with the water of right temperature that is required for the experiment. Put the thermometer into the flask with sodium thiosulphate and check the temperature is right for the experiment. If the water is too cold, in the large beaker pour in some more hot water or if it is too hot pour in some cold water to reach the required temperature for the sodium thiosulphate. Once the sodium thiosulphate is the right temperature, take it out of the water, wipe the bottom of the flask with tissue paper and place it onto the piece of paper with 'X' marked on it. Now measure 5cm³ of hydrochloric acid in the measuring cylinder. Then pour the hydrochloric acid into the sodium thiosulphate, at this moment start timing with the stopwatch and keep timing until you cannot see the 'X' mark through the liquid. Make sure you wear safety glasses and handle the acid carefully.

Fair Test:

To make this investigation fair you have to make sure you use the same concentration of hydrochloric acid for all experiments. You also have to make sure you use the same amount of hydrochloric acid and sodium thiosulphate for all the experiments. Also make sure you time the experiments accurately.

Observation:

My observation was that when the temperature of the sodium thiosulphate was higher the solution turned cloudy quicker.

Results:

Temperature (°C)

Time for cross to disappear (minutes)

20

2.49

30

.21

40

.08

50

0.29

60

0.23

Conclusion:

My conclusion is that the higher the temperature the quicker the reaction is. My evidence is shown in the table above, because 60°C takes less time than 20°C. My prediction was correct, because the higher the temperature is the faster the rate of reaction would be. To improve my experiment I would do the experiment 3 times for each temperature and then use the average of the 3 results.