(a) A solution has a pH of 7. Explain how you would :
(i) increase ist pH; (ii) decrease its pH;
(b) If a solution changes the colour of litmus from red to blue, what can you say about its pH?
(c) What can you say about the pH of a solution, that liberates carbon dioxide from sodium carbonate ?
(a) What happens when dilute hydrochloric acid is added to sodium carbonate ? Write a balanced chemical equation of the reaction involved.
(b) Which gas is liberated when dilute hydrochloric acid reacts with sodium carbonate ? How will you test for the presence of this gas ?