(a) A solultion M turns blue litmus red, so it must contain (i) hydronium ions ; another solution O turns red litmus blue and hence, must contain, (ii) hydroxide ions.
(b) When solution M and O are mixed together, the products will be (iii) salt and (iv) water.
(c) If a piece of magnesium was put into a solution M, (v) hydrogen gas would be evolved.
1. Name the apparatus ‘A’. 2. Name the substance ‘X’ placed in ‘A’ and the substance ‘Y’ placed in B. 3. State the reason for conducting the titration using the apparatus ‘A’ and ‘B’. 4. State which solution is transferred to the evaporating dish and evaporated to point of crystallization for obtaining the salt. 5. State why titration is not conducted for the preparation of copper [II] sulphate crystals by neutralization.