Quantum Mechanics Part 2

Question 1

what is the order of an absorption spectrophotometer?

Answer 1

light source —> sample —>. monochromator —> detector

Question 2

What is the order of a flourescence spectrophotometer?

Answer 2

light source + sample —-> monochromator —-> detector

Question 3

what is a monochromator?

Answer 3

a wavelength filter that accepts the polychromatic light and separates them to form a narrow band of wavelengths

Question 4

What is an example of a monochromator?

Answer 4

a prism

Question 5

how does the detector work?

Answer 5

produces an electrical current which is proportional to the power of the light falling on it, the electrical current id then displayed on a graph

Question 6

What does the absorption of infrared light lead to?

Answer 6

transitions between different vibrational energies

Question 7

Can vibrational energy ever equal zero?

Answer 7

no the molecule will always be vibrating

Question 8

How is vibrational energy placed on an energy level chart?

Answer 8

equally spaced, between excited states

Question 9

What does absorption of microwave light lead to?

Answer 9

rotational transitions

Question 10

what are the 4 steps of “creating” fluorescent light?

Answer 10

1) light is absorbed and excited to a vib. and rot. state of the first electron state
2) vib. and rot. energy is converted into heat through collision with other molecules
3) the molecule returns to its ground electronic configuration by emitting light
4) vib. and rot. energy is converted into heat through collosion with other molecules

Question 11

True or false: the wavelength of fluorescent light is shorter than the wavelength of the absorbed light

Answer 11

False; the wavelength of fluorescent light is longer than the wavelength of the absorbed light

Question 12

What is the equation for the multiplicity of spin?

Answer 12

M= 2S+1

Question 13

What does S represent in phosphorescence?

Answer 13

sum of the spin of the electrons

Question 14

True or False: Sometimes when a molecule is in the excited state it can flip the spin of an electron

Answer 14

True; this is the process if phosphorescence

Question 15

What are the six steps to phosphorescence?

Answer 15

1) light is absorbed and excited to a vib. and rot. state of the first electron state
2) vib. and rot. energy is converted into heat through collision with other molecules
3) collision flips the spin state giving the triplet spin configuration
4) vib. and rot. energy is converted into heat through collosion with other molecules
5) electron jumps back down to lower state emitting light and flips the spin to get back to the ground configuration
6) vib. and rot. energy is converted into heat through collosion with other molecules