Question

$\stackrel{\ominus }{C}{H}_3,\stackrel{\ominus }{N}{H}_2,O{H}^{\ominus },F^{\ominus }$ in increasing $p{K}_b$ values

• A. $\stackrel{\ominus }{C}{H}_3,<\stackrel{\ominus }{N}{H}_2<O{H}^{\ominus }<F^{\ominus }$
• B. $F^{\ominus }<O{H}^{\ominus }<\stackrel{\ominus }{N}{H}_2<\stackrel{\ominus }{C}{H}_3$
• C. $O{H}^{\ominus }<\stackrel{\ominus }{N}{H}_2<\stackrel{\ominus }{C}{H}_3<F^{\ominus }$
• D. none is correct

Answer 1

The correct option is A $\stackrel{\ominus }{C}{H}_3,<\stackrel{\ominus }{N}{H}_2<O{H}^{\ominus }<F^{\ominus }$

In a period, basicity of anion increases as the $p{K}_b$ value and electronegative value decreases.

Electronegativity order is
F>O>N>C

So, F being the most electronegative atom, the $p{K}_b$ value will be the highest.