Question

Phosphine is obtained by (1) $ C{{a}_{3}}{{P}_{2}}+{{H}_{2}}O\xrightarrow{{}} $ (2) $ {{P}_{4}}+NaOH\xrightarrow{{}} $ (3) $ CHC{{l}_{3}}+{{O}_{2}}\xrightarrow{{}} $ (4) $ CC{{l}_{4}}+{{O}_{2}}\xrightarrow{{}} $

• A. 1, 2 and 3 are correct.
• B. 1 and 2 are correct.
• C. 2 and 4 are correct.
• D. 1 and 3 are correct.

Answer 1

Answer: (B)

Phosphine is obtained either by treating calcium phosphite with water or by treating white phosphorus with alkali. $ \underset{\begin{smallmatrix} \,\,\,calcium \\ phosphite \end{smallmatrix}}{\mathop{C{{a}_{3}}{{P}_{2}}}}\,+6{{H}_{2}}O\xrightarrow{{}}\underset{phosphine}{\mathop{2P{{H}_{3}}}}\,+3Ca{{(OH)}_{2}} $ $ \underset{\begin{smallmatrix} \,\,\,\,\,white \\ phosphorus \end{smallmatrix}}{\mathop{{{P}_{4}}+}}\,3NaOH+3{{H}_{2}}O\xrightarrow{Warm}\underset{phosphine}{\mathop{P{{H}_{3}}}}\, $ $ +3Na{{H}_{2}}P{{O}_{2}} $