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White phosphorus ( P ₄ ) reacts with boiling aqueous NaOH solution to produce phosphine gas ( PH ₃ ) and sodium hypophosphite ( NaH ₂ PO ₂ ). Identify the correct statements regarding this reaction : (A) The equivalent weight of P ₄ in this reaction is ( Molecular weight 3 ) . (B) 0.2 moles of P ₄ produces 0.6 moles of sodium hypophosphite. (C) 62 g of P ₄ requires exactly 1.5 moles of NaOH for complete reaction. (D)

Options

  1. A(A), (B) and (C) only
  2. B(A) and (B) only
  3. C(B), (C) and (D) only
  4. D(A) and (C) only

Correct answer

A. (A), (B) and (C) only

Step-by-step solution

The balanced chemical equation for the disproportionation of white phosphorus in alkaline medium is: P ₄ + 3 NaOH + 3 H ₂ O PH ₃ + 3 NaH ₂ PO ₂ Statement (A): This is a disproportionation reaction. Oxidation half: P ₄ 4 H ₂ PO ₂⁻ (Oxidation state of P changes from 0 to +1 . Change for 4 atoms = 4 1 = 4 . So, n₁ = 4 ) Reduction half: P ₄ 4 PH ₃ (Oxidation state of P changes from 0 to -3 . Change for 4 atoms = 4 3 = 12 . So, n₂ = 12 ) Overall n-factor of P ₄ = n₁ n₂ n₁ + n₂ = 4 12 4 + 12 = 48 16 = 3 . Equivalent weig

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