You are provided with solutions BB and CC. One solution is acidic, while the other solution is basic. The acidic solution contained 3.06 g/dm3 sulphuric acid (H2SO4), while the basic solution contain 2 g of impure sodium hydroxide (NaOH) in 500 cm3 of distilled water. Perform the following procedures, and then answer the questions that follow: (i) Pour about 2 cm3 of solution BB into a test tube and use litmus paper to test if it is acidic or a basic. (ii) Discard the content and wash the test tube. (iii) Repeat the steps (i) and (ii) using solution CC. (iv) Titrate the acid solution (in the burrete) against the base solution (in the titration flask) using methyl orange (MO) as an indicator up to the end point. (v) Repeat the step (iv) to obtain three more readings and record the results in a tabular form.

1. What was the volume of the pipette used? (2 alama)
2. Calculate the average volume of the acid used to neutralize the base. (6 alama)
3. What was the colour change at the end point? (0 alama)
4. What was the colour change at the end point? (2 alama)
5. Write a balanced chemical equation for the the reaction between solutions BB and CC. (0 alama)
6. Write a balanced chemical equation for the the reaction between solutions BB and CC. (5 alama)
7. Calculate the percentage of impurity of sodium hydroxide. (0 alama)
8. Calculate the percentage of impurity of sodium hydroxide. (10 alama)

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Determine the effect of temperature on the rate of chemical reaction. Study the reaction between sodium thiosulphate and hydrochloric acid. The chemicals provided are labeled as FF, containing 0.2 M sodium thiosulphate solution and EE, containing 0.1 M hydrochloric acid solution.You are also provided with thermometer, stopwatch/ stop clock and a sheet of white paper marked X. Proceed as follows: (i) Place 50 cm3 beaker on top of cross X on the plain sheet of paper provided such that the cross X is visible through the mouth of the beaker when viewed from above. (ii) Prepare a water bath using 250 cm3 or a 300 cm3 beaker. (iii) Measure exacctly 10 cm3 of solution FF and 10 cm3 of EE and pour into separate boiling test tubes. (iv) Put the two boiling test tubes into the water bath in step (ii) and warm the contents to 40oC. (v) Pour the hot solutions FF and EE into the 50 cm3 beaker in step (i) and immediately start the stopwatch/clock. Record the time taken in seconds for the cross to disappear completely. (vi) Repeat the procedures stated in (iii) to (v) at different temperatures of 50oC, 60oC and 70oC and record your readings as shown in the following table. Table: Experimental Data Temperature (0C) Time (sec) 1 /time (Sec−1) 40 50 60 70

1. Complete filling the table. (0 alama)
2. What does 1/time in the table represent? (0 alama)
3. Write a balanced chemical equation for the reaction between EE and FF. (0 alama)
4. What is the name of the product causing the solution to turn cloudy making the letter X to disappear? (0 alama)
5. Plot graph of temperature against 1/time (0 alama)
6. From the graph what do you conclude about the effect of increasing temperature on the rate of reaction? (0 alama)

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