Question

Volume of hydrogen required for complete hydrogenation of 0.25dm cube of ethyne at STP

Answer 1

Hydrogenation of ethyne complete in two process :-

1) C2H2 + H2 → C2H4
2)C2H4 + H2 → C2H6

==========================
add this ,
C2H2 + 2H2 → C2H6

hence, for 1 mole hydrogenation of ethyne 2 mole of H2 is require

so, 22.4 L , hydrogenation of C2H2 , 2×22.4 L of H2 is require

so, 0.25 L , hydrogenation of C2H2 2× 0.25 L of H2 is require

hence, 0.5 L or 05 dm³ volume of H2 is require.

note : - 1 L = 1dm³

Answer 2

Hydrogenation of ethyne complete in 2 process:- 1) C2H2 + H2 = C2H4 2) C2H4 + H2 = C2H6 Now add this, C2H2 + H2 = C2H6 Hence, for 1 mole hydrogenation of ethyne 2 mole of H2 is require So, 22.4 L hydrogenation of C2H2, 2 × 22.4 L H2 is require So, 0.25 L, hydrogenation of C2H2 2×0.25L of H2 is require Hence 0.5 L OR 0.5 dm^3 volume of H2 is require Note 1 L = 1dm^3