$A$ reagent consisting of $1$-naphthylamine and sulphanilic acid in acetic acid is used for the detection of:

$A$ solution of a salt in dilute $H_2SO_4$ gives a blue color with starch iodide solution. This indicates the presence of which ion?

Which of the following anions cannot be tested by $dil. H_2SO_4$?

Which of the following silver precipitates dissolves in $dil. \, HNO_3$ to produce a clear solution?

Which reagent below would enable you to remove sulphate ions from a solution containing both sulphate and chloride ions?

$A$ chloride salt solution acidified with dil. $HNO_3$ gives a curdy white precipitate,$[A]$,on addition of $AgNO_3$. $[A]$ on treatment with $NH_4OH$ gives a clear solution,$B$. Identify $[A]$ and $B$.