Question

The dipole moment of ${H_2}{O_2}$ is $2.1D$ while that of water is $1.84D$ . but water $({H_2}O)$ is a better solvent than that of ${H_2}{O_2}$ because:
(A) Its dipole moment is less than that of ${H_2}{O_2}$
(B) It is less corrosive.
(C) ${H_2}{O_2}$ gets ionized during chemical reactions.
(D) ${H_2}{O_2}$ gets decomposed during chemical reactions.

Answer 1

We know that Dipole moment is caused when there is a difference between the electronegativities of two atoms bonded in a chemical compound. It measures the polarity of a chemical compound. So, the more the dipole moment of a chemical compound the more will be its solubility.

Complete step-by-step answer: In water molecules we know that lone pairs are localized around the oxygen atom because oxygen is much more electronegative than hydrogen. Therefore, the presence of lone pairs on the oxygen atom gives it a bent shape so the individual dipole moment does not cancel each other and hence the net dipole moment of water is found to be $1.84D$
However, ${H_2}{O_2}$ is thermally unstable and it decomposes easily.
Here is the decomposition reaction of ${H_2}{O_2}$:
${H_2}{O_2}(l) \to {H_2}O(l) + \dfrac{1}{2}{O_2}(g)$
Also, it cannot be used as a solvent because of its strong auto oxidation ability. It acts as an oxidizing agent as weak bonds are present between the oxygen atoms which breaks easily and releases radicals.

Therefore, the correct answer is Option D i.e. ${H_2}{O_2}$ gets decomposed during chemical reactions.

Note: ${H_2}{O_2}$ is very difficult to work with as it is very corrosive in nature. It can cause damage to eyes, skin and respiratory system. A dipole moment arises where there is a difference of charges, therefore it can arise in ionic as well as in covalent bonds.