When a solution becomes more acidic, does the pH get higher or lower?

35 Separate the following into substances having pH values above and below 7. How do these influence litmus paper?

(i) Lemon juice

(ii) Solution of washing soda

(iii) Toothpaste

(iv) Vinegar

(v) Stomach juices

36 Do basic solutions also have H⁺ (aq) ions? If yes, then why are they basic? 37 Define an acid and a base. Give two examples of each. 37 Give the names and formulae of two strong bases and two weak bases.