Moderate

Phosphene gas will be produced if phosphorous acid is subjected to___________________?

Correct answer: D. Both b & c

  • A. Oxidation
  • B. Reduction
  • C. Decomposition
  • D. Both b & c

Explanation

H3PO3 undergoes disproportionation on heating: some phosphorus(III) is oxidised to phosphorus(V) in H3PO4, while some is reduced to phosphorus(-III) in PH3. Therefore the process is both oxidation-reduction and decomposition, making “both b and c” correct; oxidation alone is the likely distractor because it ignores PH3 formation.

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About Redox Reactions

Redox reactions involve oxidation and reduction occurring together, with electrons transferred between species or oxidation numbers changing. The topic covers assigning oxidation states, identifying oxidizing and reducing agents, balancing redox equations by oxidation number or half-reaction methods, and connecting chemical changes with galvanic and electrolytic cells.

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