The document provides instructions to calculate the Coulomb energy for NaCl at its equilibrium separation. It states that the Coulomb energy at equilibrium is given by the equation Ueq = -1/4πε0(e2/R), where e is the elementary charge, ε0 is the vacuum permittivity, and R is the equilibrium separation distance between Na and Cl. It then provides the values to use in the calculation, resulting in a Coulomb energy of -8.9556 eV.

1. 1
Calculate the Coulomb
energy for NaCl at its
equilibrium separation.
Helping Tools
No.1

2. 2

3. 3
No.2

4. 4

5. 5
No.3

6. 6
Solution

7. 7
2
0
We know that at equilibrium
separation Coulomb energy
is given as:
1
4
1.44 .
1.7476
0.281
8.9556
C
eq
e
U X
R
eV nm
nm
eV


= −
= −
= −