Topic 7- Modern analytic techniques

Question 1

Define the molecular ion peak

Answer 1

indicates the species formed from the molecule by the loss of one electron (the peak furthest to the right on a mass spectrum)

Question 2

What is fragmentation?

Answer 2

it occurs when the molecular ion breaks into smaller pieces

Question 3

What’s the base peak?

Answer 3

indicates the peak with the greatest abundance

Question 4

Define infrared radiation

Answer 4

the part of the electromagnetic spectrum with frequencies below red light

Question 5

When does stretching occur?

Answer 5

when a bond absorbs infrared radiation and uses it to alter the length of the bond

Question 6

What is meant by the transmittance value?

Answer 6

the transmittance value in an infrared spectrum represents the amount of radiation absorbed at a particular wavenumber

Question 7

What’s the wavenumber of an infrared absorption?

Answer 7

represents the frequency of infrared radiation absorbed by a particular bond in a molecule

Question 8

What is meant by the intensity of an infrared absorption?

Answer 8

describes the amount of infrared radiation absorbed

Question 9

When a molecule absorbs infrared radiation, what does the amount of energy absorbed depend on?

Answer 9

• the length of the bond
• the strength of the bond
• the mass of each atom involved in the bond