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An organic compound ‘A’ is oxidized with N a 2 O 2 followed by boiling with H N O 3 . The resultant solution is then treated with ammonium molybdate to yield a yellow percipitate. Based on a above observation, the element present in the given compound is:

Options

  1. AFluorine
  2. BPhosphorus
  3. CNitrogen
  4. DSulphur

Correct answer

B. Phosphorus

Step-by-step solution

The phosphorus containing organic compounds are detected by 'Lassaigne's test' by heated with an oxidizing agent (sodium peroxide). The phosphorus present in the compound is oxidised to phosphate. The solution is boiled with nitric acid and then treated with ammonium molybdate to produced canary yellow precipitate. Phosphorus gets oxidised when it is treated with fuming conc. H N O 3 . Na 3 PO 4 + 3 H N O 3 → H 3 P O 4 + 3 NaNO 3 Phosphoric acid is used along with molybdenum compound for the ident

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