Consider Two Adjacent Water Molecules in an Ice Crystal

Multiple Choice

Consider two adjacent water molecules in an ice crystal. Assume that the binding energy connecting them follows a Lennard-Jones potential with a potential well depth of 9.6x10-21 J, and the equilibrium atomic spacing is 3.196x10-10 m. How much force must you apply to one of the molecules to increase the separation of the two atoms by 10% from the equilibrium spacing? Assume that the other molecule is fixed in position.

A) 3.0x10-11 N
B) 5.4x10-11 N
C) 8.0x10-11 N
D) 3.2x10-10 N
E) 9.6x10-10 N