Q1-For an ion pair of potassium chloride (KCl),K+Cl, attractive and repulsive energies EA and ER respectively, depend on the distance between the ions r, according to EA=r1.63ER=r95.39106 For these expressions, energies are expressed in electron volts (eV) per the ion (K+Cl9 pair, and r is the distance in nanometers (nm). The net energy EN is just the sum of the two expressions above. (a) Mathematically determine the equilibrium spacing r0 and the magnitude of the bonding energy E0 between the two ions. (Class work) (b) Graphically determine the equilibrium spacing r0 and the magnitude of the bonding energy E0 between the two ions ( r from 0.15 to 1.0nm with 0.001 increment). ( 20 points)