The absorption of infrared (IR) radiation results in vibrations in the molecules or ions that make up a chemical sample. a. True
b. False

True

Explanation:

Infrared spectroscopy is concerned with transitions between vibrational energy levels in molecules.

The vibrations that are found to be infrared active in molecules are those vibrations that result in a change of dipole moment in the molecule.

In the treatment of infrared spectroscopy, the covalent bond is treated as an elastic spring which can be stretched. The approach of the simple harmonic oscillator can be applied to the problem.

a. a primary source combines several different accounts of an event. b. a primary source generally benefits from having been written after an event.

explanation:

the answer is:  

line graphs show patterns in data with variables that change over time; whereas, circle graphs show data as parts out of a whole (such as out of 100%).