8.4. The effect of temperature on the rate of reaction, p224.

S₂O₃^2-_(aq)+2H⁺_(aq)SO_2(aq)+S_(s)+H₂O_(l)

Apparatus:

400cm³ beaker full of water              A sheet of paper with white spot on it

2 boiling tubes                                   2 statives with clamping equipment

2 20cm³ labelled measuring cylinders 100cm³ of 0.50M HCl

100 cm³ 0.10M sodium thiosulphate   2 200cm³ beakers

Thermometer           Timer               Bunsen burner               Labels(4)          Matches

Procedure:

1.     Put the tubes into the beaker so that they are half - immersed and connect the Bunsen burner.

2.     Put the paper with the dot behind beaker A.

3.     Add acid to B and thiosulphate to A (label cylinders and beakers).

4.     Wait a bit when the temperature of water = temperature of reactants.

5.     Add acid quickly to thiosulphate, start timer, stir with thermometer and record temp. =      

6.     Measure the time for the dark spot to disappear completely time =                      

7.     Repeat first 6 in different temperatures given below.

rate =. Activation energy is a tangent of 1/T against ln(rate).