How will you distinguish between
(i) `Na_(2)CO_(3)` and `NaHCO_(3)` and (ii) `LiNO_(3)` and `KNO_(3)` ?

Explanation

(i) `NaHCO_(3)` on heating decomposes to produce `CO_(2)` gas which turns lime water milky
`2 NaHCO_(3) overset(Delta)(to) Na_(2)CO_(3) + CO_(2) + H_(2)O`
`Na_(2)CO_(3)` , however , is stable to heat .
(ii) `LiNO_(3)` on heating gives reddish brown vapours of `NO_(2)` whereas `KNO_(3)` on decomposition gives colourless `O_(2) ` gas .
`4 LiNO_(3) overset(Delta)(to) 2 Li_(2)O + 4NO_(2) + O_(2) " " , 2 KNO_(3) overset(Delta)(to) 2 KNO_(2) + O_(2)`