A sodium salt of unknown anion when treated with MgCl_(2) gives white precipitateonly on boiling . The anion is

A sodium salt of unknown anion when treated with MgCl_(2) gives white

1.	A sodium salt of unknown anion when treated with MgCl_(2) gives white precipitateonly on boiling . The anion is
Answer» `SO_(4)^(2-)` `HCO_(3)^(-)` `CO_(3)^(2-)` `NO_(3)^(-)` Solution :BICARBONATES on heating FORM insoluble CARBONATES `MgCl_(2) + 2 NaHCO_(3) to NaCl + Mg(HCO_(3))_(2)` `Mg(HCO_(3))_(2) OVERSET(Delta)(to) MgCO_(3) darr + CO_(2) + H_(2)O`