Potential energy as a function of r is given by U = A r 10 - B r 5 , where r is the interatomic distance, A and B are positive constants. The equilibrium distance between the two atoms will be :

Step-by-step solution

Given U = A r 10 - B r 5 . Now, for equilibrium, d U d r = 0 . So, differentiating the given equation, - 10 A r 11 + 5 B r 6 = 0 ⇒ 10 A r 11 = 5 B r 6 ⇒ r 5 = 2 A B ⇒ r = 2 A B 1 5