Question

Bond energy of covalent $O-H~$ bond in water is:
A. greater than bond energy of hydrogen bond
B. equal to bond energy of hydrogen bond
C. less than bond energy of hydrogen bond
D. half of the bond energy of hydrogen bond

Answer 1

Hint: The amount of energy required to break a bond is called the bond energy of that bond. Thus the stronger bond needs more energy to break and have high bond energy.

Complete step by step solution:The Conditions for making hydrogen bonds are as follows-
The molecule must contain a highly electronegative atom that is attached to the hydrogen atom to form a covalent bond. Higher the electronegativity more is the polarization of the molecule so that electrons of the covalent bonds are shifted towards the more electronegative atom and make partially positive charged hydrogen atom.
Smaller the size of the electronegative atom, the greater is the electrostatic attraction. Thus hydrogen bond is a weak bond formed due to van der waals’ force of attraction.
Covalent bond is formed due to sharing of electron pair between two atoms. Thus in water the oxygen and hydrogen atom share their electrons to complete their octet and forms a strong bond.
Thus we can write that the bond energy of the covalent \[O-H~\] bond in water is greater than the bond energy of hydrogen bond.

Thus the correct option is A.

Note: Bond energy of a pure covalent bond is higher than any type of bond. Again bond energy of double and triple bond is higher than a pure single covalent bond.