question_answer

    If\[F{{e}^{3+}}\]and\[C{{r}^{3+}}\]both are present in group III of qualitative analysis, then distinction can be made by:

A)  addition of\[N{{H}_{4}}OH\]in presence of\[N{{H}_{4}}Cl\]when only\[Fe{{(OH)}_{3}}\]is precipitated

B)  addition of\[N{{H}_{4}}OH\]in presence of\[N{{H}_{4}}Cl\]when\[Cr{{(OH)}_{3}}\]and\[Fe{{(OH)}_{3}}\]both are precipitated and on adding\[B{{r}_{2}}\]water and \[NaOH,Cr{{(OH)}_{3}}\]dissolves

C)  precipitate of\[Cr{{(OH)}_{3}}\]and\[Fe{{(OH)}_{3}}\]as obtained in  are treated! with cone.\[HCl\] when only\[Fe{{(OH)}_{3}}\]dissolves

D)   and (b) the (c) correct.