Base strength of
`(1) H_(3)Coverset(Theta)(C)H_(2), (2) H_(2)C=overset(Theta)(C)H` and (3) `H-C-=overset(Theta)(C)` is in the order of

Options

A. (i) gt (iii) gt (ii)
B. (i) gt (ii) (iii)
C. (ii) gt (i) gt (iii)
D. (iii) gt (ii) gt (i)

Answer

B

Explanation

`underset(sp)(H-C)-=underset(sp)(C-H)gt underset(sp^(2))(CH_(2))=underset("(Acidic character)")(underset(sp^(2))(CH_(2))gt underset(sp^(3))(CH_(3))-underset(sp^(3))(CH_(3)))`
Conjugate base of the given acid is as follows :
`C^(Theta)C-Hlt ^(Theta)CHCH_(2)lt underset("(Basic character)")(.^(Theta)CH_(2)-CH_(3))`
So conjugate base of stronger acid is weaker and vice-versa.