What is observed when hot concentrated caustic soda solution is added to

(a) Zinc

(b) Aluminium?

Write balanced equations.

Distinguish by adding: Sodium hydroxide solution or ammonium hydroxide solution to

(a) Calcium salt solution and lead salt solution

(b) Lead nitrate solution and zinc nitrate solution

(c) Copper salt solution and ferrous salt solution

(d) Fe(II) salt solution and Fe(III) salt solution

(e) Ferrous nitrate and lead nitrate

You are provided with two reagent bottles marked A and B. One contains NH₄OH solution and the other contains NaOH solution. How will you identify them by a chemical test?