4) (Extra Credit) A function that looks like a realistic molecular potential is the Morse Potential. (see eqn 8 .4 in the text): V(x) = De(l e'' )2 Expand V(x) in a Taylor series about 11:0 to obtain U(x) = D8 [321:2 De 133.153 +A Given that, for HCl, De=7.3 11:10'19 J/molecule, and [3:1.55321r1010 m'l, calculate the force constant for HCl. Use Excel, Python, or another computer package to plot the Morse potential and the corresponding H.0. potential on the same graph. (in other words, make your own version of Fig. 8.6). 5) (Extra Credit) In 2-3 sentences, based on your work in (4) explain why you think we encounter the harmonic oscillator potential so frequently in chemistry and physics problems? Comment on what Situations you think the H .0. would be a bad approximation