5(a) \[ 2\mathrm{Na}_{2}\mathrm{CrO}_{4}+2\mathrm{H}^{+} \rightarrow \underset{\text{(A)}}{\mathrm{Na}_{2}\mathrm{Cr}_{2}\mathrm{O}_{7}}+2\mathrm{Na}^{+}+\mathrm{H}_{2}\mathrm{O} \]
\[ \text { (Yellow) } \underset{(\mathrm{A})}{\text { Orange }} \]
\[ \underset{\text { (A) }}{\mathrm{Na}_{2}\mathrm{Cr}_{2} \mathrm{O}_{7}}+\underset{\text { (conc.) }}{2 \mathrm{H}_{2} \mathrm{SO}_{4}} \rightarrow \underset{\substack{\text { Bright orange } \text { solid }}}{2 \mathrm{CrO}_{3}}+2 \mathrm{NaHSO}_{4}+\mathrm{H}_{2} \mathrm{O} \]
\[ \underset{\text { (A) }}{\mathrm{Na}_{2} \mathrm{Cr}_{2} \mathrm{O}_{7}}+\underset{\text { (C) }}{4 \mathrm{Cl}^{-}}+\underset{\text { (conc.) }}{6 \mathrm{H}_{2} \mathrm{SO}_{4}} \rightarrow \underset{\text { (deep red liquid) }}{\mathrm{CrO}_{2} \mathrm{Cl}_{2}}+2 \mathrm{NaHSO}_{4}+4 \mathrm{HSO}_{4}^{-}+3 \mathrm{H}_{2} \mathrm{O} \]
\[ \text{So,} \begin{array}{l} \mathrm{A} \equiv \mathrm{Na}_{2} \mathrm{Cr}_{2} \mathrm{O}_{7} \mathrm{B} \equiv \mathrm{CrO}_{3} \mathrm{C} \equiv \mathrm{Cl}^{-} \end{array} \]
(a)(Yellow) Orange
(b)Na 2CrO7 2H 2SO4 2CrO3 2NaHSO 4 H 2O
(c)(conc.) (B) Bright orange solid Na 2Cr2O7 4Cl 6H 2SO 4 CrO2Cl2 2NaHSO 4 4HSO 4 3H 2O
(d)(C) (conc.) (deep red liquid) So, A Na 2Cr2 O7 B CrO3 C Cl chemistry (IIT-JAM) 215 emission 211 emission 211