In the test for halogens,why is nitric acid a | vedclass

Name: Exam Paper Generator | JEE NEET Paper Generator | Vedclass
Brand: Vedclass
Rating: 5 (35 reviews)

Question

(B) The sodium fusion extract often contains sodium cyanide $(NaCN)$ and sodium sulphide $(Na_2S)$ if nitrogen and sulphur are present in the organic

Vedclass · Accepted Answer

To decompose sodium cyanide and sodium sulphide,which interfere with the test.

Vedclass · Answer

(B) The sodium fusion extract often contains sodium cyanide $(NaCN)$ and sodium sulphide $(Na_2S)$ if nitrogen and sulphur are present in the organic compound. If $AgNO_3$ is added directly,these ions would form precipitates like $AgCN$ and $Ag_2S$,which interfere with the halide test. Adding $HNO_3$ decomposes these species: $NaCN + HNO_3 \rightarrow NaNO_3 + HCN \uparrow$ $Na_2S + 2HNO_3 \rightarrow 2NaNO_3 + H_2S \uparrow$ This ensures that only the halide ions ($Cl^-$,$Br^-$,$I^-$) react with $Ag^+$ to form the characteristic silver halide precipitate.

In the test for halogens,why is nitric acid added to the sodium fusion extract before adding silver nitrate?

Similar Questions

Statement $I$: Nitrogen in pyridine cannot be estimated by Kjeldahl’s method. Statement $II$: Nitrogen in pyridine changes to ammonium sulphate when heated with conc. $H_2SO_4$ in Kjeldahl’s method. Read the above given statements and choose the correct answer from the given options.

Identify the binary mixture$(s)$ that can be separated into individual compounds by differential extraction,as shown in the given scheme.
$(A)$ $C_6H_5OH$ and $C_6H_5COOH$
$(B)$ $C_6H_5COOH$ and $C_6H_5CH_2OH$
$(C)$ $C_6H_5CH_2OH$ and $C_6H_5OH$
$(D)$ $C_6H_5CH_2OH$ and $C_6H_5CH_2COOH$

Why is the test for nitrogen,sulphur,or halogens not carried out by the direct addition of reagents to an organic compound?

An organic compound on heating with $CuO$ produces $CO_{2}$ but no water. The organic compound may be

In Lassaigne's test for the detection of halogens,the sodium fusion extract is first boiled with concentrated nitric acid. This is

Vedclass Test Series

Exam Paper Generator

Online Exam Module