Fill in the blank with the correct choice given in the bracket —
The salt prepared by the method of direct combination is …………… [iron [II] chloride / iron [III] chloride]

Three solutions P, Q, and R have pH value of 3.5, 5.2 and 12.2 respectively. State which one of these is a:

(i) weak acid

(ii) strong alkali

Give the appropriate term defined by the statement given :
The substance that releases hydronium ion as the only positive ion when dissolved in water.

The pH values of three solutions A, B, C are given .

Solution A : pH value 12

Solution B : pH value 2

Solution C : pH value 7

Answer the following questions :

(i) Which solution will have no effect on litmus solution.

(ii) Which solution will liberate CO₂ when reacted with sodium carbonate.

(iii) Which solution will turn red litmus solution blue.