Quantum Theory

Question 1

Spectroscopy

Answer 1

The method for finding out about the structure of molecules that depends on the interaction of molecular compounds with radiation.

Question 2

Absorption Spectrum

Answer 2

A plot of radiation energy versus the percentage of radiation transmitted

Question 3

Frequency

Answer 3

“nu” - the number of wave peaks that pass by a fixed point per until time.

Question 4

Wavenumber

Answer 4

The number of repeating units of a wave in a unit of space (rather than time). This is a reciprocal of frequency.

Question 5

What happens when molecules absorb microwaves?

Answer 5

Molecular tumbling

Question 6

What happens when molecules absorb ultraviolet light?

Answer 6

Covalent bonds can rupture

Question 7

What happens when molecules absorb infrared light?

Answer 7

Molecular vibration

Question 8

How do atoms become excited?

Answer 8

Atoms absorb energy.

Question 9

How do atoms return to their ground state?

Answer 9

Atoms release their extra energy by emission of radiation.

Question 10

Line Emission Spectrum

Answer 10

Excited atoms emit only particular wavelengths of light - when this light is passed through a prism, only a few coloured lines are seen.

Question 11

What does it mean for the energy of electrons to be quantized?

Answer 11

They can only have particular amounts of energy and not values between the “allowed” levels.

Question 12

Lyman Series

Answer 12

A series of emission lines having energies in the ultraviolet region.

Question 13

Balme Series

Answer 13

A series of emission lines have energies in the visible region.

Question 14

What is the l value for the s orbital?

Answer 14

0

Question 15

What is the l value for the p orbital?

Answer 15

1

Question 16

What is the l value for the d orbital?

Answer 16

2

Question 17

What is the l value for the f orbital?

Answer 17

3

Question 18

What orbital has the l value of 0?

Answer 18

s orbital

Question 19

What orbital has the l value of 1?

Answer 19

p orbital

Question 20

What orbital has the l value of 2?

Answer 20

d orbital

Question 21

What orbital has the l value of 3?

Answer 21

f orbital

Question 22

What is an orbital?

Answer 22

Refers to a mathematical function, which is one part of the solution to the wave equation for each stationary wave. Non-uniform distributions of electron matter over space around the nucleus.

Question 23

Orbitals of an atom that have been derived by use of the same value of n in the Schrodinger equation are said to be in the same _____.

Answer 23

Shell

Example: The 2s orbital (n=2, l=0) and the three 2p orbitals (n=2, l=1) are all part of the same n=2 shell.

Question 24

In a given shell, each set of orbitals derived by use of a particular value of l in the Schrodinger equation are said to be in the same ________.

Answer 24

Sub-shell

Example: in the n=3 shell, the 3s subshell is comprised of the 3s orbital (l=0,m1 =0)

Question 25

What type of wave is an electron?

Answer 25

A standing wave

Question 26

How can you find the number of orbitals in a sub-shell?

Answer 26

2(L) + 1

Question 27

How many orbitals in sub-shell s?

Answer 27

1

Question 28

How many orbitals in sub-shell p?

Answer 28

3

Question 29

How many orbitals in sub-shell d?

Answer 29

5

Question 30

How many orbitals in sub-shell f?

Answer 30

7

Question 31

Diamagnetic

Answer 31

Substances that are slightly repelled by a magnet

Question 32

Paramagnetic

Answer 32

Substances that are attracted to a magnetic field. They have unpaired electrons.

Question 33

What is the shape of s orbitals?

Answer 33

They are spherically symmetrical.

Question 34

Principal QN n

Answer 34

n = 1,2,3...

Question 35

How do you find the density of the electron wave?

Answer 35

Wavefunction^2

Question 36

As the principal QN n increases, the number of nodes in a wavefunction ____________.

Answer 36

increases

Question 37

At a node, the sign of the wavefunction is _______.

Answer 37

zero

Question 38

On either side of a node, the sign of the wavefunction __________.

Answer 38

changes phase

Question 39

A node is a region of _______ electron density.

Answer 39

zero

Question 40

Radial node

Answer 40

a region of zero electron density that exists at a specific radial distance from the nucleus. In 3D a radial node is a sphere, but a 2D cross section represents such a node as a circle.

Question 41

Angular Node

Answer 41

a plane of zero electron density that exists at a specific angle from a particular axis. In 3D, a angular node is a plane, but 2D cross section represents such a node as a line

Question 42

The total number of nodes depends on principal QN n, and is equal to _____.

Answer 42

n-1

Question 43

As the principal quantum number increases, the orbital size ___________.

Answer 43

increases

Question 44

In an s-orbital, the angular QN, l, is always equal to______.

Answer 44

zero

Question 45

In an s-orbital, the number of angular nodes is always equal to ______.

Answer 45

zero

Question 46

In a p-orbital, the angular QN, l, is always equal to ____.

Answer 46

one

Question 47

In a p-orbital, the number of angular nodes is always equal to ____.

Answer 47

one

Question 48

In both s and p orbitals, the number of angular nodes equals _____.

Answer 48

l

Question 49

The number of angular nodes in a d-orbital is always equal to _______.

Answer 49

two

Question 50

The value of the principal QN n determines the number of _________ nodes.

Answer 50

total

Question 51

The value of the principal QN n determines the ______ of the orbital.

Answer 51

size

Question 52

The value of the angular QN l determines the number of ________ nodes.

Answer 52

angular

Question 53

The value of the angular QN l determines the ______ of the orbitals.

Answer 53

shape

Question 54

How do you find the energy of an electron at a certain energy state?

Answer 54

Equation: E = -(1/n^2)RH

Question 55

What is the equation for wavelength of a photon?

Answer 55

"lambda" = hc/E

Question 56

What is the equation for wavelength of a particle?

Answer 56

"lambda" = h/mv

Question 57

How many atomic orbitals are in the sub-shell with quantum numbers n = 6 and l =2?

Answer 57

Five. This is a 6d orbital. All d orbitals have 5 orbitals.