Ch 6: Quantum Theory and the Electronic Structure of Atoms

Question 1

Traditional cancer treatment therapies involve the use of powerful ionizing radiation, such as X rays or _____ rays. Ionizing radiation damages the ___ of cancer cells, preventing their continued replication – although it does the same to healthy, noncancerous cells.

Answer 1

gamma
DNA

Question 2

Photodynamic therapy works by irradiation with visible light, which is far less _________ than X-ray or gamma radiation, and thus safer to use. Treatment begins with the administration of a photosensitizer (a substance that undergoes reaction when irradiated) that is ___________ taken up by cancerous tissue. Subsequent irradiation with a specific wavelength of visible light causes the photosensitizer to produce an especially reactive form of oxygen known as _______ oxygen, which damages the cancerous cells and prevents further replication.

Answer 2

energetic
selectively
singlet

p. 233

Question 3

When we say “light”, we generally mean visible light, which is the light we can detect with our eyes. Visible light, however, is only a small part of the continuum of radiation that makes up the __________ spectrum.

Answer 3

electromagnetic

p. 214

Question 4

Wavelength (λ) is defined as…

Answer 4

….the distance between identical points on successive waves.

Question 5

frequency (“nu”, ν) is defined as…

Answer 5

…the number of waves that pass through a particular point in 1 second.

Question 6

amplitude is defined as…

Answer 6

…the vertical distance from the midline of a wave to the top of the peak or the bottom of the trough

Question 7

In 1873, who proposed that visible light is composed of electromagnetic waves?

Answer 7

James Clerk Maxwell

Question 8

What is Planck’s constant?

Answer 8

The value is 6.63 x 10^-34 J·s

In 1900, Max Planck …

Question 9

What is the relationship between energy and wavelength?

Answer 9

energy and wavelength are INVERSELY proportional, because of these equations:

E = hν

c = λν

Question 10

When using Planck’s constant to calculate the de Broglie wavelength of a “particle”, what units should this constant have (in order to cancel with other units and get a wavelength in m?)

Answer 10

kg•m²/s

Question 11

The principal quantum number (n) designates….

The principal quantum number can have integral values of 1, 2, 3, and so forth, and it corresponds to the quantum number in Bohr’s model of the hydrogen atom.

Answer 11

…the size of the orbital.

Question 12

The angular momentum quantum number (ℓ) describes…

Answer 12

…the shape of the atomic orbital

Question 13

The magnetic quantum number m_<u>l</u> describes…

Answer 13

…the orientation of the orbital in space

Question 14

To specify the electron’s spin, we use the electron spin quantum number ( m_<u>s</u> ) . Because there are two possible directions of spin, opposite each other, m_s has two possible values:

___ and ___. Two electrons in the same orbital with opposite spins are referred to as “______.”

Answer 14

+½ and -½

paired

Question 15

The values of ℓ are integers that depend on the value of the principal quantum number, n. For a given value of n, the possible values of ℓ range from _ to ___. If n=1, there is only one possible value of ℓ**; that is, 0 (n−1 where n=1).

If n=2, there are two values of ℓ: 0 and 1. If n=3, there are three values of ℓ: 0, 1, and 2.

Answer 15

0 to n-1

Question 16

The value of ℓ is designated by the letters s, p, d, and f, where s corresponds to a value of ℓ equal to….

Answer 16

• ℓ=0*
• ℓ=1*
• ℓ=2*
• ℓ=3*

Question 17

What is the electron configuration for Neon?

Answer 17

1s²2s²2p⁶

Question 18

What is the electron configuration for Argon?

Answer 18

1s²2s²2p⁶3s²3p⁶

Question 19

What does the Aufbau principle state?

Answer 19

An e^- always goes into the next available orbital with the lowest energy.

Question 20

What does the Pauli exclusion principle state?

Answer 20

No more than 2 e-‘s can occupy each atomic orbital. The electrons must be of opposite spin.

Question 21

What does Hund’s principle state?

Answer 21

When there are two or more atomic orbitals with the same energy, an e^- will occupy this before it will pair up with another electron.

Question 22

Is the ENERGY of particular type of radiation directly proportional to the wavelength of the wave or the frequency?

Answer 22

Energy = hν

Therefore, energy is directly proportional to FREQUENCY.

Question 23

Order the following types of electromagnetic radiation according to INCREASING frequency/energy.

visible light

microwave

radio waves

ultraviolet

gamma rays

infrared

x-rays

Answer 23

radio waves < microwaves < infrared < visible light < ultraviolet light < X rays < gamma rays

Question 24

What mnemonic can you use to help you remember the range of electromagnetic radiation in order of decreasing frequency (increasing wavelength)?

Answer 24

Get Xtra Umbrellas. Vera Is Making Rain!

Gamma rays (10²⁰ Hz)

X-rays (10¹⁸)

Ultraviolet light (10^15-16 Hz; so named bc it has a higher frequency than visible light)

Visible light (10¹⁴ Hz; 400-700 nm)

Infrared (10¹³ Hz; so named bc it has a lower frequency than visible light)

Microwaves (~10¹⁰ Hz)

Radio waves (~10⁶ Hz)

Question 25

In regard to stationary waves, some points on a guitar string, for example, are called _____, and do not move at all. There is a node at each end, and there may be one or more nodes between the ends. The greater the frequency of vibration, the shorter the __________ of the standing wave and the greater the number of nodes. According to de Broglie, an electron in an atom behaves like a standing wave.

Answer 25

nodes

wavelength

p. 250

Question 26

De Broglie argued that if an electron does behave like a standing wave in the hydrogen atom, the wavelength must fit the circumference of the orbit exactly; that is, the circumference of the orbit must be an ________ _______ of the wavelength. Otherwise, the wave would partially cancel itself by destructive interference on each successive orbit, quickly reducing its amplitude to zero. What equation gives the relationship between the circumference of an allowed orbit (2∏r), and the wavelength (λ) of the electron?

Answer 26

integral multiple

2∏r = nλ

(r is the radius of the orbit, λ is the wavelength of the electron wave, and n is a positive integer (1, 2, 3, …). Because n is an integer, r can have only certain values (integral multiples of λ) as n increases from 1 to 2 to 3 and so on. And, because the energy of the electron depends on the size of the orbit (or the value of r), the energy can have only certain values too. Thus, the energy of the electron in a hydrogen atom, if it behaves like a standing wave, must be quantized.)

Question 27

What formula do we need to know in order to calculate the de Broglie wavelength or mass of a particle?

Answer 27

λ = h / mu

(u in this formula is velocity in m/s; also, mass must be in kg for units to cancel correctly.)

Question 28

The “m∗u” part of the previous equation can also give us the _______ of a particle. This quantity (or vector rather) has units of kg∗m/s, or N∗s.

(Remember that a N is a derived SI unit: 1 N = 1 kg∗m/s²)

Answer 28

momentum

Question 29

What calculating the ΔE of an atom undergoing transition between levels, if ΔE is +, a photon will be ________. If ΔE is -, a photon will be _______.

Answer 29

absorbed

emitted

Question 30

As electrons go from a lower energy level to a higher energy level, they get AHED, which stands for…..

Answer 30

Absorb light (or energy)

Higher potential

Excited

Distant (from the nucleus)

[mnemonic from Kaplan Gen Chem Review, p. 13]

Question 31

A collection of orbitals with the same value of n is frequently called a ____. One or more orbitals with the same n and ℓ values are referred to as a _______.

Answer 31

shell

subshell