Question 19-21

Summary: 19. Name and evaluate the effect of a type of galvanic cell in terms of chemistry and impact on society. 20(a) State one way in which pH can be measured. (b) Explain why solutions of equal concentrations of hydrochloric acid and citric acid have different pH values. 21(a) Name the type of reaction when barium hydroxide and sulfuric acid react. (b) Explain the changes shown in a graph measuring the conductivity of a sample of barium hydroxide when titrated with sulfuric acid. (Note that part (b) is not in the current course.)