QQuestion
Differentiate between the following pairs of compounds using the reagent given in the bracket:
(a) Ammonium chloride and Sodium chloride (using an alkali)
(b) Zinc Nitrate solution and Calcium Nitrate solution (using excess sodium hydroxide solution)
✓Answer
(a) When ammonium chloride is reacted with an alkali like NaOH, the colourless gas ammonia having a sharp pungent characteristic smell is evolved. Whereas, sodium chloride (NaCl) does not show any reaction with alkali.
\mathrm{NH_4Cl + NaOH \rightarrow NH_3 \uparrow + NaCl + H_2O} \mathrm{NaCl + NaOH \rightarrow No\ reaction}(b) Add sodium hydroxide (NaOH) solution first drop by drop and then in excess.
Zinc Nitrate solution: A white gelatinous precipitate of zinc hydroxide forms, which dissolves in excess NaOH to give a clear solution.
Calcium Nitrate solution: A white precipitate of calcium hydroxide forms and remains insoluble even in excess NaOH.
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