Question

The most polar bond is

• A. $Br-H$
• B. $Cl-H$
• C. $O-H$
• D. $N-H$

Answer 1

Answer: (C)

More the difference in electronegativities of elements, more polar will be the bond.
$\begin{array}{llcc}Br-H& \Delta X=2.8-2.1\Rightarrow & 0.7& \\ Cl-H& \Delta X=3.0-2.1& \Rightarrow & 0.9\\ O-H& \Delta X=3.5-2.1& \Rightarrow & 1.4\\ N-H& \Delta X=3.0-2.1& \Rightarrow & 0.9\end{array}$