Question

The infrared spectrum above represents the absorption of certain wavelengths of radiation by molecules of CO2. Which of the following best explains what occurs at the molecular level as the CO2 molecules absorb photons of the infrared radiation?

Answer 1

Answer:

Carbon Dioxide is an Infrared Radiation Absorber. The (CO2) molecules also emits the absorbed infrared (IR) radiation energy. The photon energy from the infrared radiation causes the CO2 molecule to vibrate. Only some of its vibrational modes absorb infrared radiation

Explanation:

Its linear structure is considered when working with the formula to calculate the number of molecular vibrational modes. It has 3n - 4 vibrational modes, where n is the number of atoms in a compound of CO2

With 3 atoms, CO2 has

3n−5=4 types or patterns of vibration

1. The symmetric stretch

2. The asymmetric stretch

3. The bend

The symmetric stretch vibrational mode is ir-inactive.

The asymmetric stretch is ir-active as it results in changes in dipole moment

The bend is ir-active as well as it results in a change in dipole moment too.