4. Write each exponential equation in logarithmic form. a. y: 7" (1 mark) b. x = 36y (1 mark) 5. Write each logarithmic equation in exponential form. a. y = logx (1 mark) h. y=log5x (1 mark) 6. The pH of a solution can be determined using the formula pH = log[H +], where H + is the hydrogen ion concentration in the solution. a. The hydrogen ion concentration of a solution is 0.012 mol/L. Calculate the pH of the solution, to the nearest tenth. (1 mark) b. A baking soda solution has a pH of 7.8. Algebraically determine the hydrogen ion concentration of this solution. Show all your work and express your answer in scientic notation to the nearest tenth. (2 marks) 7. Write the numerical value of each logarithmic expression. Round to the nearest hundredth if necessary. (2 marks 0.4 marks each) a. log7 65 b. 11110 c. log3 100 d. log10+log100 e. 2log510log54