Q. The most acidic hydrogen atoms are present in
Solution:
The acidity of hydrogen atoms is directly proportional to the presence of s-character
Compound
Chemical Formula
Hybridisation
$\%$ s-character
Ethane
$CH _{3}- CH _{3}$
$sp ^{3}$
$25 \%$
Ethene
$CH _{2} =CH _{2}$
$sp ^{2}$
$33.33 \%$
Ethyne
$CH\equiv CH$
$sp$
$50 \%$
Benzene
$C _{6}H _{6}$
$sp ^{2}$
$33.33 \%$
Since, Ethyne has highest percentage of s-character, hence, most acidic hydrogen atoms are present in ethyne.
| Compound | Chemical Formula | Hybridisation | $\%$ s-character |
| Ethane | $CH _{3}- CH _{3}$ | $sp ^{3}$ | $25 \%$ |
| Ethene | $CH _{2} =CH _{2}$ | $sp ^{2}$ | $33.33 \%$ |
| Ethyne | $CH\equiv CH$ | $sp$ | $50 \%$ |
| Benzene | $C _{6}H _{6}$ | $sp ^{2}$ | $33.33 \%$ |