How many of the following are correct.
(i) A white precipitate is obtained when a solution of `BaCl_(2)` is treated with `Na_(2)SO_(3)`
(ii) A white precipitate is obtained when a solution of `NaAlO_(2)` is heated with `NH_(4)Cl`
(iii) A white precipitate is obtained when `H_(2)SO_(4)` is passed through a solution of `ZnSO_(4)`
(iv) A white precipitate is obtained when a solution of `ZnSO_(4)` is treated with one of `Na_(2)CO_(3)`

Answer

1,2,4

Explanation

`(i) BaCl_(2)+Na_(2)SO_(3)rarr undeset("white")(BaSO_(3))+2NaCl`
`(ii) NaAlO_(2)+NH_(4)ClrarrNH_(3)uarr +underset("white")(NaCl)+Al(OH)_(3)`
`(iii) ZnSO_(4)+H_(2)S rarr ` No reaction
`(iv) Na_(2)CO_(3)+ZnSO_(4)rarrZnCO_(3)+underset("whiteppt")(Na_(2)SO_(4))`