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The Lassaigne’s extract is boiled with dil. HNO 3 before testing for halogens because,

1. Silver halides are soluble in HNO 3
2. Ag 2 S is soluble in HNO 3
3. Na 2 S and NaCN are decomposed by HNO 3
4. AgCN is soluble in HNO 3

Correct answer: Na 2 S and NaCN are decomposed by HNO 3

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