The blue color obtained in the Lassaigne's te | vedclass

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Question

(D) In Lassaigne's test for nitrogen,the sodium fusion extract contains sodium cyanide $(NaCN)$.When this extract is treated with ferrous sulfate $(Fe

Vedclass · Accepted Answer

$Fe_4[Fe(CN)_6]_3$

Vedclass · Answer

(D) In Lassaigne's test for nitrogen,the sodium fusion extract contains sodium cyanide $(NaCN)$.When this extract is treated with ferrous sulfate $(FeSO_4)$,sodium ferrocyanide is formed: $6NaCN + FeSO_4 \rightarrow Na_4[Fe(CN)_6] + Na_2SO_4$.On adding ferric chloride $(FeCl_3)$,the ferric ions react with the ferrocyanide ions to form ferric ferrocyanide,which is Prussian blue in color: $3Na_4[Fe(CN)_6] + 4FeCl_3 \rightarrow Fe_4[Fe(CN)_6]_3 + 12NaCl$.Thus,the blue color is due to the formation of $Fe_4[Fe(CN)_6]_3$.

Column $I$	Column $II$
$A. H_2N-NH_3^+Cl^-$	$p. \text{Sodium fusion extract of the compound gives Prussian blue colour with } FeSO_4$
$B. HO-C_6H_4-CH(NH_3^+)COOH \text{ (with } I^- \text{ counterion)}$	$q. \text{Gives positive } FeCl_3 \text{ test}$
$C. HO-C_6H_4-NH_3^+Cl^-$	$r. \text{Gives white precipitate with } AgNO_3$
$D. (NO_2)_2C_6H_3-NH-NH_3^+Br^-$	$s. \text{Reacts with aldehydes to form the corresponding hydrazone derivative}$

The blue color obtained in the Lassaigne's test is due to the formation of which compound?

Similar Questions

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