Question

Both ionic and covalent bonds are present in

• A. $\mathrm{KCl}$
• B. $\mathrm{NaOH}$
• C. ${\mathrm{CH}}_4$
• D. ${\mathrm{SO}}_2$

Answer 1

The correct option is B

$\mathrm{NaOH}$

Explanation for Correct option:

(B) $\mathrm{NaOH}$

• The ionic bond is formed between the positive and negative ions i.e ${\mathrm{Na}}^{+}\&{\mathrm{OH}}^{-}$
• Whereas, the covalent bond between the oxygen and hydrogen $\mathrm{O}\&\mathrm{H}$.
• The covalent bond is formed by the mutual sharing of electrons. and ionic bonds formed by electronegative atoms attract the electropositive atom. So, this is the correct option.

Explanation for incorrect options:

(A) $\mathrm{KCl}$

• There is an ionic bond between potassium ions and chloride ions ${\mathrm{K}}^{+}\&{\mathrm{Cl}}^{-}$. No other bond is present. So, this is an incorrect answer.

(C) ${\mathrm{CH}}_4$

• There is a covalent bond between the carbon and four hydrogen atoms. So, this is an incorrect option.

(D) ${\mathrm{SO}}_2$

• There is a polar covalent bond between sulphur and oxygen atoms. So, this is an incorrect option.

Hence, the molecule has both bonds i.e ionic and covalent sodium hydroxide (B) $\mathrm{NaOH}$.