when beta-carotene is oxidised in vivo, it breaks in half and forms two molecules of retinal (vitamin A). which is a precurser to the pigment in the retina responsible for vision. The conjugated system of retinal consist of 11 C and one O atom. in the ground state of retinal, each level up to n=6 is occupied by 2 electrons. Assuming an average internuclear distance of 140 pm.

A) calculate the seperation in Energy between the ground state and the first excited state in which one electron occupies the state with n=7.

B) The frequency of the radiation required to produce a transition between these two states.

C) using your results, chooce among the words in perentheses to generate a rule for the pridiction of frequency shifts in the absorbtion spectra of linear polyenes:

1- The absorbtion spectrum of a linear polyene shifts to (higher/lower) frequency as the number of conjugated atoms (increace/decrease).