The correct order of increasing basicity of the given conjugate bases `(R=CH_(3))` is :

Options

A. `RCOoverline(O)ltoverline(N)H_(2)lt-=overline(C)ltoverline(R)`
B. `RCOoverline(O)ltHC-=overline(C)ltoverline(N)H_(2)ltoverline(R)`
C. `RCOoverline(O)ltHC-=overline(C)ltoverline(R)ltoverline(N)H_(2)`
D. `overline(R)ltHC-=overline(C)ltRCOoverline(O)ltoverline(N)H_(2)`.

Answer

B

Explanation

Stronger the acid , weaker is the conjugate base. Base + proton `to` Conjugate acid Conjugate acids formed in the given question will be : `RCOOH,NH_(3),HC-=CH,CH_(4)`
Acidic strength follows order : `RCOOHgtHC-=CHgtNH_(3)gtCH_(4)`
`therefore` Basicity of conjugate bases : `RCOO^(-)ltHC-=C^(-)lt""^(-)NH_(2)ltR^(-)`