White phosphorus is heated with concentrated NaOH in CO ₂ atmosphere to form a gas A and compound B . When A is bubbled into aqueous CuSO ₄ solution copper phosphide and C are formed, B and C are respectively

Step-by-step solution

(i) When white phosphorus is heated with concentrated NaOH in inert atmosphere of CO ₂ , it gives PH ₃(g) and NaH ₂ PO ₂ as follows : aligned & P ₄+3 NaOH +3 H ₂ O CO ₂ (A) PH ₃(g) & + 3 NaH ₂ PO ₄ & (Sodium hypophosphite) & aligned (B) ii) When (A) , i.e. PH ₃(g) is bubbled into aqueous CuSO ₄ solution, copper phosphide ( Cu ₃ P ₂ ) and H ₂ SO ₄( C ) is formed. The reaction occurs as follows : 2 PH ₃+3 CuSO ₄ array c ( Copper phosphide) array Cu ₃ P ₂ +3 H ₂ SO ₄ Hence, (B)= NaH ₂ PO ₂,(C)= H ₂ SO ₄ Hence, option