The table shows experimental data. Table: Experimental data | Experiment No. | Volume of NN (cm³) | Volume of LL (cm³) | Time (sec) | |----------------|--------------------|--------------------|------------| | 1 | 10 | 10 | 15 | | 2 | 10 | 15 | 10 | | 3 | 10 | 20 | 5 | (a) Complete filling the experimental table. (b) What does represent in the experimental table? (c) Write a balanced chemical equation for the reaction between LL and NN. (d) How was the factor of concentration varied in this experiment? (e) Plot a graph of volume of solution LL against time. (f) Use the graph you have drawn in (e) above to explain how the variation of concentration affects the rate of chemical reaction.

1. Describe the procedure you would follow to determine the molar mass of the unknown solid using solution B. (7 mk)
2. What was the volume of the pipette used? (0 mk)
3. Complete filling the experimental table. (0 mk)
4. What was the colour change at the end point? (0 mk)
5. Perform the titration calculations using the following results obtained from the experiment. Table 1: Titration of 25.0 cm³ of solution A against solution B. | Titre No. | Initial burette reading (cm³) | Final burette reading (cm³) | Volume of solution B used (cm³) | |-----------|-----------------------------------|----------------------------------|--------------------------------------| | 1 | 0.0 | 20.5 | 20.5 | | 2 | 20.5 | 40.8 | 20.3 | | 3 | 40.8 | 61.1 | 20.3 | Average volume of solution B used = 20.3 cm³ Assume that the unknown solid is a monoprotic acid. (18 mk)
6. What does represent in the experimental table? (0 mk)
7. Calculate the average volume of the acid used to neutralize the base. (0 mk)
8. Write a balanced chemical equation for the reaction between LL and NN. (0 mk)
9. How was the factor of concentration varied in this experiment? (0 mk)
10. Plot a graph of volume of solution LL against time. (0 mk)
11. Use the graph you have drawn in (e) above to explain how the variation of concentration affects the rate of chemical reaction. (0 mk)

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You are provided with the following: LL: A solution of 0.13 M Na^S203 (sodium thiosulphate); NN: A solution of 2 M HC1; Distilled water, Stopwatch or stop clock; A sheet of white paper marked X. Procedure Measure 20 cm of solution LL and put it into a 100 cm' beaker. (i) Place the beaker containing solution LL on the top of a letter X drawn on a sheet of paper. (ii) Measure 10 cm* of NN; pour it into a beaker containing solution LL and immediately start (ii) the stopwatch. Swirl the beaker with contents twice. (iv) Look down vertically through the mouth of the beaker so as to see the cross at the bottom of the beaker. Stop the clock when the letter X is invisible. ((Vv) ) Record the time taken for the letter X to disappear completely. (vi) Repeat the experiment using the data shown in the following table. Find this aPnadg oeth e2r forefe3 re sources at: e022

1. Describe how you would prepare a standard solution of approximately 0.05 M copper (II) sulphate from solution C. (5 mk)
2. You are asked to investigate the reaction between copper (II) sulphate and sodium sulphite. Describe the procedure you would follow and the observations you expect to make. (15 mk)
3. Explain the observations made in (b) and write the relevant ionic equation. (5 mk)

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