A sodium salt of an unknown anion when treated with MgCl2 gives white precipitate only on boiling. The anion is

Question

A sodium salt of an unknown anion when treated with MgCl2 gives white precipitate only on boiling. The anion is (A)  SO42-  (B)  HCO3-  (C)  CO32-  (D)  NO3-

Tardigrade Admin · Accepted Answer

Mg ( HCO 3)2 on boiling decomposes to give white precipitate of MgCO 3 as: Mg ( HCO 3)2(a q) xrightarrow text Heat MgCO 3 downarrow+ H 2 O + CO 2 uparrow

Q. A sodium salt of an unknown anion when treated with $M g C l_{2}$ gives white precipitate only on boiling. The anion is

$S O_{4}^{2 -}$

$H C O_{3}^{-}$

$C O_{3}^{2 -}$

$N O_{3}^{-}$

$M g (H C O_{3})_{2}$ on boiling decomposes to give white precipitate of $M g C O_{3}$ as:
$M g (H C O_{3})_{2} (a q) Heat M g C O_{3} ↓ + H_{2} O + C O_{2} ↑$

Q. A sodium salt of an unknown anion when treated with MgCl2​ gives white precipitate only on boiling. The anion is

SO42−​

HCO3−​

CO32−​

NO3−​