The reaction of white phosphorus with aqueous NaOH gives phosphine along with another phosphorus containing compound. The reaction type ; the oxidation states of phosphorus in phosphine and the other product are respectively :The reaction of white phosphorus with aqueous NaOH gives phosphine along with another phosphorus containing compound. The reaction type ; the oxidation states of phosphorus in phosphine and the other product are respectively :

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Question

The reaction of white phosphorus with aqueous NaOH gives phosphine along with another phosphorus containing compound. The reaction type ; the oxidation states of phosphorus in phosphine and the other product are respectively :The reaction of white phosphorus with aqueous NaOH gives phosphine along with another phosphorus containing compound. The reaction type ; the oxidation states of phosphorus in phosphine and the other product are respectively :

disproportionation reaction ; – 3 and +5

redox reaction ; – 3 and – 5

redox reaction; + 3 and +5

disproportionation reaction ; –3 and + 3

3NaOH + P₄ + 3H₂O $\to_{}^{}$ PH₃(–3) + 3NaH₂PO₂(+1)

H₂PO₂^– + 2OH^– $\to_{}^{}$ 2H₂ + PO₄^3– (+5)

The reaction of white phosphorus (P₄) with aqueous sodium hydroxide (NaOH) produces phosphine (PH₃) and sodium hypophosphite (NaH₂PO₂). The balanced chemical equation is:

$P_{4} + 3 NaOH + 3 H_{2} O \to PH_{3} + 3 NaH_{2} {PO}_{2}$

This is a disproportionation reaction because phosphorus in white phosphorus (oxidation state 0) is both oxidized and reduced. In phosphine (PH₃), phosphorus has an oxidation state of -3 (reduction), and in hypophosphite ion (H₂PO₂^-), phosphorus has an oxidation state of +1 (oxidation). However, note that the options provided include +5, -5, +3, and -3. The correct oxidation states for this reaction are -3 in PH₃ and +1 in H₂PO₂^-, but since +1 is not an option, and the question asks for the values from the given options, the intended answer is -3 and +5, but that is incorrect for this reaction. Actually, the other product is hypophosphite, not phosphate. There might be a confusion. In some conditions, white phosphorus with alkali can give phosphine and phosphate, but the standard reaction with NaOH gives hypophosphite.

Upon rechecking, the reaction is: P₄ + 3NaOH + 3H₂O → PH₃ + 3NaH₂PO₂. The oxidation state of P in NaH₂PO₂ is +1. But the options do not have +1. However, in the problem, it says "another phosphorus containing compound", which is hypophosphite, but the options suggest phosphate (with P=+5). There might be a mistake in the options or the question. Typically, this reaction is disproportionation with P oxidation states changing from 0 to -3 and +1.

Given the options, the correct choice is "disproportionation reaction ; –3 and +5" because it is the only one with disproportionation and -3, and +5 might be a misprint for +1, but in the context, it is accepted as +5 for phosphate, though not accurate. Actually, with concentrated NaOH and heat, P₄ can give phosphine and phosphate, but the equation is different: P₄ + 3NaOH + 3H₂O → PH₃ + 3NaH₂PO₂ is standard. To get phosphate, it requires different conditions.

For the purpose of this question, based on the options, the answer is disproportionation reaction with oxidation states -3 and +5, assuming the other product is phosphate (though it is hypophosphite in reality). So, the reaction type is disproportionation, oxidation state in PH₃ is -3, and in the other product (considered as phosphate) is +5.

Step-by-step reasoning:

Step 1: Identify the reaction: White phosphorus (P₄) with NaOH produces PH₃ and NaH₂PO₂ (hypophosphite).

Step 2: Determine the oxidation state of phosphorus in reactants and products. In P₄, oxidation state is 0. In PH₃, let oxidation state of P be x: x + 3*(+1) = 0, so x = -3. In H₂PO₂^-, let oxidation state of P be y: 2*(+1) + y + 2*(-2) = -1 (charge), so 2 + y -4 = -1, y -2 = -1, y = +1.

Step 3: Since the same element (P) is both oxidized (from 0 to +1) and reduced (from 0 to -3), it is a disproportionation reaction.

Step 4: Compare with options: The correct option should be "disproportionation reaction ; –3 and +1", but since +1 is not there, and +5 is given, it might be an error. However, in some sources, it is stated that the other product has P in +5 state, which is incorrect. But for the given options, the closest is "disproportionation reaction ; –3 and +5".

So, the answer is the first option: disproportionation reaction ; –3 and +5.

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