1. Why are π to π * transitions on conjugated double bonds such good absorbers of
visible light?
2. Intensity of the HeNe laser (λ=632nm) was measured at 2 distances: 1 m and 200 m
from the laser. The meter reading was 10W and 1 W correspondingly. How many
photons/sec will enter your eye if you look into the laser from 1 m? From 200 m?
Assume that radius of the pupil was 2.5 mm, radius of the detector was 3.5 mm. At a
distance of 1 m the laser beam radius was 1 mm.
3. Chl has an absorbance peak at 435nm (Soret band) and a peak at 665nm
(Qytransition). Calculate the energy gap (in Joules) between the ground and excited
states of these two transitions.
Any help in the right direction would be great thanks!
