Chapter 7 Quantum

Question 1

What is the electromagnetic spectrum?

Answer 1

A continuous range of radiant energy
Shortest to longest wavelengths:
Gamma rays, X-rays, ultraviolet, visible light, infrared, microwave, radio

Question 2

What is the photoelectric effect?

Answer 2

It is the phenomenon of light striking a metal surface and producing an electric current (flow of electrons)
If radiation is below threshold energy (v not), no electrons are released
-photons of sufficient energy (hv) dislodge e- from metal surface

Question 3

What is the de Broglie wavelength?

Answer 3

It is the wavelength associated with a moving particle

Question 4

What is the Heisenberg uncertainty principle?

Answer 4

We only know the probability of an electrons location.

Question 5

What is the Schrodinger wave equation and what is its solution?

Answer 5

It is the variation of electron matter wave with time and location of electron in an atom
Its solution is the wave funciton

Question 6

What is the Schrodinger wave equation and what is its solution?

Answer 6

It is the variation of electron matter wave with time and location of electron in an atom
Its solution is the wave function

Question 7

What are the quantum numbers?

Answer 7

Principle quantum number:
Angular momentum quantum number:
Magnetic quantum number
Electron spin quantum number

Question 8

What does the principle quantum number indicate?

Answer 8

n indicating relative size and energy of orbital or group of orbitals- same n same shell, generally, increase n increase energy level

Question 9

What does the angular momentum quantum number indicate?

Answer 9

l, 0 to n-1, shape of orbital
same n and l means same subshell and equal energy levels

Question 10

What does the magnetic quantum number indicate?

Answer 10

M (subscript) l, integer from - l to + l, orientation of orbital in space around nucleus of an atom

Question 11

What is the Pauli exclusion principle?

Answer 11

No two electrons in a multielectron atom can have the same set of four quantum numbers.

Question 12

What does the M (subscript) s quantum number indicate?

Answer 12

Electron spin- either = +1/2 o r-1/2

Question 13

What is the aufbau principle?

Answer 13

Fill the lowest energy orbital first

Question 14

What is Hund’s rule?

Answer 14

The lowest-energy in degenerate orbitals is the maximum number of unpaired parallel valence electrons.

Question 15

What is the trend of atomic radii?

Answer 15

The radii increases down a column and decreases across a row

Question 16

What is the trend of ionization energy?

Answer 16

The ionization energy increases left to right and decreases top to bottom

Question 17

What does the wave function describe?

Answer 17

The motion of electron waves as they vary with location and time

Question 18

What does the wave function squared describe?

Answer 18

An orbital or region of high probability for locating an electron

Question 19

What part of the atom makes its radii larger?

Answer 19

Electrons
Repulsion increases the radii
Attraction decreases the radii

Question 20

How do the radii of cations and anions compare to the radii of their parent atoms?

Answer 20

Cations are smaller
Anions are larger

Question 21

Atomic radius:

Answer 21

Half the distance between identical nuclear centers in a molecule

Question 22

Metallic radius:

Answer 22

Half the distance between nuclear centers in the solid metal

Question 23

Ionic radius

Answer 23

Derived from the distance between nuclear centers in solid ionic compound

Question 24

Who discovered the quantum theory? What experiment was used?

Answer 24

Mac plank who used blackbody radiation (radiation from very hot objects) experiments to determine that radiant energy can only be emitted or absorbed in small quantities, like packets or bundles

Question 25

What were the benefits of Bohrs model?

Answer 25

Accurately predicted ionization energy and allowed scientists to use the quantum theory to explain matter at the atomic level

Question 26

What were the limitations of Bohrs model?

Answer 26

It did not account for multielectron spectra and did not explain the electron movement clearly