Task 1. Determination of the dependence of transmission coefficient on the thickness of substance

Layer.

1. Plug photoelectrocolorimeter to the network, the signal bulb has to be lit. Leave the colorimeter for 15 minutes with the opened cover of cuvette section.

2. Place two cuvettes in the cuvette section. One is empty and the second one with 50 mm length is filled with researched solution. Empty cuvette is placed to the farthest receptacle of cuvette holder and the filled one to the nearest receptacle. Deviation of handle to the left – light bundle goes to the empty cuvette, to the right – to the cuvette with researched liquid.

3. Close the cover of cuvette section.

4. Direct the light bundle to the empty cuvette.

5. Set the arrow of apparatus to 1000 exactly and roughly using set “100” handle. Introduce the light bundle in the cuvette with solution by the turning of handle to the right.

6. Write down the apparatus readings that correspond to the transmission coefficient T(%) of the solution.

7. Conduct the experiment 3 times. Determine the transmission coefficient of researched solution as average from obtained data.

8. Determine the transmission coefficient for cuvettes with 30, 20, 10, 5 mm length using the same method. Put the data into the table.

Transmission coefficient Т (%)

Table 1.

9. Construct a graph Т=f(l) using the obtained data (horizontal axis is for the length and the vertical one is for the transmission coefficient).