Question

. When infrared radiation is absorbed by molecules what is the effect it has on the molecule? Is it bond breaking ? or   ionization ? or rotation ? or vibration ? or kinetic energy ? or increase in pressure ? or increase in temperature ?   If more than one please indicate which.

Answer 1

Solution: The absorption of infrared radiation corresponds to energy changes on the order of 8 to 40 kJ/mole. Radiation is in this energy range corresponds to the range encompassing the stretching and bending vibrational frequencies of the bonds in most covalent molecules. In the absorption process, those frequencies of infrared radiation that match the natural vibrational frequencies of the molecule in question are absorbed, and the energy absorbed serves to increase the amplitude of the vibrational motions of the bonds in the molecule.