Answer to Question #282387 in Physical Chemistry for Nur

Question

Which one of the following energy levels are occupied upon absorption of UV-Vis energy?

1. Excited V0

2. Excited V1

3. Ground state V2

A) 1 and 3

B) 1 and 2

C) only 2

D) 2 and 3

E) 1,2 and 3

Answer 1

Ultraviolet and visible radiation interacts with matter which causes electronic transitions (promotion of electrons from the ground state to a high energy state). The ultraviolet region falls in the range between 190-380 nm, the visible region fall between 380-750 nm.

The following electronic transitions are possible:

π- π* (pi to pi star transition)

n - π* (n to pi star transition)

Therefore upon absorption of UV-Vis energy:

1. Excited V0

2. Excited V1

energy levels are occupied.