Practical Chemistry Question 6
Question 6 - 2024 (30 Jan Shift 1)
The Lassiagne’s extract is boiled with dil $HNO _3$ before testing for halogens because,
(1) $AgCN$ is soluble in $HNO _3$
(2) Silver halides are soluble in $HNO _3$
(3) $Ag _2 S$ is soluble in $HNO _3$
(4) $Na _2 S$ and $NaCN$ are decomposed by $HNO _3$
Show Answer
Answer (4)
Solution
If nitrogen or sulphur is also present in the compound, the sodium fusion extract is first boiled with concentrated nitric acid to decompose cyanide or sulphide of sodium during Lassaigne’s test
