Qualitative Analysis - Result Question 10
####10. A solution when diluted with $H _2 O$ and boiled, it gives a white precipitate. On addition of excess $NH _4 Cl / NH _4 OH$, the volume of precipitate decreases leaving behind a white gelatinous precipitate. Identify the precipitate which dissolves in $NH _4 OH / NH _4 Cl$.
(a) $Zn(OH) _2$
(b) $Al(OH) _3$
(c) $Mg(OH) _2$
(d) $Ca(OH) _2$
(2006, 3M)
Show Answer
Solution:
- $Zn^{2+}+2 H _2 O \longrightarrow \underset{\text { White }}{Zn(OH) _2 \downarrow} \downarrow+2 H^{+}$
