Question

Which of the following compound(s) has /have percentage of carbon same as that in ethylene (C2H4)
(a) propene
(b) ethyne
(c) benzene
(d) ethane

Answer 1

Mσʅαɾ ɱαʂʂ σϝ ƚԋҽ Eƚԋყʅҽɳҽ
= 12 × 2 + 1 × 4
= 24 + 4
= 28 ɠ/ɱσʅҽ.

Mαʂʂ σϝ ƚԋҽ CαɾႦσɳ Pɾҽʂҽɳƚ ιɳ Eƚԋყʅҽɳҽ
= 12 × 2 
= 24

∴ % ƈσɱρσʂιƚισɳ σϝ CαɾႦσɳ
= 24/28 × 100
= 85.71 %

ᴍᴏʟᴀʀ ᴍᴀss ᴏғ ᴛʜᴇ ᴘʀᴏᴘᴇɴᴇ(ᴄ₃ʜ₆)
= 12 × 3 + 1 × 6
 = 36 + 6
 = 42 ɢ/ᴍᴏʟᴇ.

ᴍᴀss ᴏғ ᴛʜᴇ ᴄᴀʀʙᴏɴ ᴘʀᴇsᴇɴᴛ ɪɴ ᴛʜᴇ ᴘʀᴏᴘᴇɴᴇ
= 36 ɢ.

% ᴄᴏᴍᴘᴏsɪᴛɪᴏɴ ᴏғ ᴄ
= 36/42 ×100
 = 85.71 %

% ᴄᴏᴍᴘᴏsɪᴛɪᴏɴ ᴏғ ᴛʜᴇ ᴄ ɪs sᴀᴍᴇ ᴀs ᴘʀᴏᴘᴇɴᴇ.

thank you ♥