Question

The potential energy (y) curve for H₂ formation as a function of internuclear distance (x) of the H atoms is shown below.

The bond energy of H₂ is

(1) (c – a) 

(2) (b – a)

(3) $(c – a)\over2$

(4) $(b – a)\over2$

Comments

Chemical bonding and molecular structure

Answer 1

Ans: (2) (b – a)

Sol. 

• Potential energy of two H atoms at infinite distance = a
• Potential energy of two H atoms at distance equal to bond length = b

BE = (b – a)

Answer 2

Correct ans is (b-a)