Q. Given below are two statements : Statement I : One mole of propyne reacts with excess of sodium to liberate half a mole of H₂ gas. Statement II : Four g of propyne reacts with NaNH₂ to liberate NH₃ gas which occupies 224 mL at STP. In the light of the above statements, choose the most appropriate answer from the options given below:
A) Statement I is incorrect but Statement II is correct
B) Both Statement I and Statement II are correct
C) Statement I is correct but Statement II is incorrect
D) Both Statement I and Statement II are incorrect
Explanation
[Solution by Dr. Abubacker] Propyne has one acidic ≡C–H: 2 CH₃C≡CH + 2 Na → 2 CH₃C≡CNa + H₂, so 1 mol gives 0.5 mol H₂ (I is correct). 4 g of propyne (M = 40) is 0.1 mol and gives 0.1 mol NH₃ = 2240 mL at STP, not 224 mL (II is incorrect). Answer (3).
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.