please assist question 4 only

6 [21 Marks) Question 4 ACID-BASE EQUILIBRIUM & SOLUBILITY EQUILIBRIUM 4.1 (a) What is the significance of pH = 7? 4.1 (b) How does the pH change as oH is added to the solution? (1) (1) 2] 4.2 (a) In a sample of lemon juice the (H+) is 3.8 x 10-6 M. What is the pH? 4.2 (b) A sample of freshly pressed apple juice has a pH of 3.76. Calculate the [H*). een as De (2) (2) [4 4.3 (a) If the poH for a solution is 3.00, what is the pH of the solution? 4.3 (b) is the solution acidic or basic? (2) (1) [3] 4.4 What is the pH of a buffer solution that is 0.15 M chloroacetic acid and 0.10 M sodium chloroacetate? ik, = 1.3 x 109). [4] 4.5 What is the concentration of hydroxide ion in a 0.060 M aqueous solution of methylamine, CH3NH2 (Ko = 4.4 x 10") ? What is the pH? Use the ICE table in your calculation. Test your assumption if you make one during your calculation. [8] Question 5 CHEMICAL KINETICS [20 marks] 5.1 Hydrogen sulphide burns in oxygen to form sulphur dioxide and water. If sulphur dioxide is being formed at a rate of 0.30 mol Li's', what are the rates of disappearance of hydrogen and oxygen? [6] 5.2 Nitrogen monoxide, NO, reacts with hydrogen to give nitrous oxide, N20, and water. 2NO(g) + H2(g) N2O(g) + H2O(g) In a series of experiments, the following initial rates of disappearance of NO were obtained