3. Energies 100 kcal/mol= 4.3 eV= 286 nm= 35000 /cm (near UV) nano= 10-9 286 kcal/mol= 12.4 eV= 100 nm= 100000 /cm (far UV) Typical Bond Energies C-H = 110 kcal/mol C-C = 80 C=C = 150 C=O = 170 Uv light 150 -40 nm wavelength, so this is sufficient energy to break bonds –knock electrons out of bonding orbitals (electronic excitation).

6. A Jablonski diagram, named after the Polish physicist AleksanderJabłoński, is a diagram that illustrates the electronic states of a molecule and the transitions between them. The states are arranged vertically by energy and grouped horizontally by spin multiplicity. Radiative transitions are indicated by straight arrows and nonradiative transitions by squiggly arrows. The vibrational ground states of each electronic state are indicated with thick lines, the higher rotational states with thinner lines.

10. Chemical Processes undergone by Excited Molecules