Question:
The Lassaigne's extract is boiled with conc. $HNO_3$ while testing for halogens. By doing so it
The Lassaigne's extract is boiled with conc. $HNO_3$ while testing for halogens. By doing so it
Updated On: May 25, 2026
- helps in the precipitation of $AgCl$
- increases the solubility product of $AgCl$
- increases the concentration of $NO^-_3$ ions
- decomposes $Na_2S$ and $NaCN$, if formed
Show Solution
Verified By Collegedunia
The Correct Option is D
Solution and Explanation
Na$_2$S and NaCN, if present in the extract, will be
decomposed to H$_2$S and HCN by HNO$_3$ .
NaCN + HN$O_3$ $\rightarrow$ NaN$O_3$ + HCN
Na$_2$S + 2HNO$_3$ $\rightarrow$ 2NaN$O_3$ + H$_2$S
These will escape from the solution and will not
interfere with the test for halogens.
decomposed to H$_2$S and HCN by HNO$_3$ .
NaCN + HN$O_3$ $\rightarrow$ NaN$O_3$ + HCN
Na$_2$S + 2HNO$_3$ $\rightarrow$ 2NaN$O_3$ + H$_2$S
These will escape from the solution and will not
interfere with the test for halogens.
Was this answer helpful?
0
0
Top NEET Chemistry Questions
- The unit of rate constant for zero order reaction is
- The number of geometrical isomers of $CH_{3} CH=CH-CH=CH-CH=CHCl$ is
- A $100.0\, mL$ dilute solution of $Ag ^{+}$is electrolysed for $15.0$ minutes with a current of $1.25 \,mA$ and the silver is removed completely. What was the initial $\left[ Ag ^{+}\right]$?
- Trans esterification is the process of
- A given metal crystallizes out with a cubic structure having edge length of 361 pm. If there are four metal aotms in one unit cell, what is the radius of one atom?
View More Questions
Top NEET Methods Of Purification Of Organic Compounds Questions
Top NEET Questions
- A coil of inductive reactance $31\, \Omega$ has a resistance of 8 $\Omega$. It is placed in series with a condenser of capacitative reactance $25 \,\Omega$. The combination is connected to an a.c. source of 110 V. The power factor of the circuit is :-
- In an a.c. circuit with phase voltage V and current I, the power dissipated is
- A bubble in glass slab $ (\mu = 1.5) $ when viewed from one side appears at 5 cm and 2 cm from other side, then thickness of slab is
- A bulb is located on a wall. Its image is to be obtained on a parallel wall with the help of convex lens. If the distance between parallel walls is 'd' then required focal length of lens placed in between the walls is : -
- A convex lens is dipped in a liquid whose refractive index is equal to the refractive index of the lens. Then its focal length will
View More Questions
Concepts Used:
Purification of Organic Compounds
We commonly use these methods for the purification of substances:
- Simple crystallization - The most common method that we use to purify organic solids.
- Fractional crystallization - It is the process of separation of different components of a mixture by repeated crystallisations.
- Sublimation - Certain organic solids on heating directly change from solid to vapor state without passing through a liquid state. These substances are sublimable. This process is sublimation.
- Simple distillation - It is the joint process of vaporization and condensation.
- Fractional distillation - It is the process to separate a mixture of two or more miscible liquids which have boiling points close to each other
- Distillation under reduced pressure
- Steam distillation
- Azeotropic distillation
- Chromatography