The Lassaigne's extract is boiled with dil ${\rm{HN}}{{\rm{O}}_3}$ before testing for halogens because

${\rm{N}}{{\rm{a}}_2}{\rm{S}}$ and ${\rm{NaCN}}$ are decomposed by ${\rm{HN}}{{\rm{O}}_3}$

AGCN is soluble in ${\rm{HN}}{{\rm{O}}_3}$

Silver halides are soluble in ${\rm{HN}}{{\rm{O}}_3}$

${\rm{A}}{{\rm{g}}_2}{\rm{S}}$ is soluble in ${\rm{HN}}{{\rm{O}}_3}$

JEE CHEMISTRY MCQ: ORGANIC CHEMISTRY-SOME BASIC PRINCIPLES AND TECHNIQUES

1 Easy

1 of 1

Understanding +4 | -1

The Lassaigne's extract is boiled with dil

\mathrm{HN}{\mathrm{O}_3}

before testing for halogens because

View answer and explanation

Correct option: C

\mathrm{N}{\mathrm{a}_2}\mathrm{S}

and

\mathrm{NaCN}

are decomposed by

\mathrm{HN}{\mathrm{O}_3}

Option C (

\mathrm{N}{\mathrm{a}_2}\mathrm{S}

and

\mathrm{NaCN}

are decomposed by

\mathrm{HN}{\mathrm{O}_3}

) is correct because

Na_2S

and

NaCN

interfere with the halogen test by forming

Ag_2S

and

AgCN

precipitates, respectively, which are not silver halides.