Quantum Theory & Atomic Structure

Question 1

A _____ is a discrete, quantized bundle of electromagnetic energy.

Answer 1

PHOTON

Question 2

Name one use of the Photoelectric effect.

Answer 2

solar panels

garage door sensors

nightlights

Question 3

The ____ ____ is the region in which there is a high probability of finding an electron.

Answer 3

Electron Cloud

However, the highest probability to find electrons are in their orbitals.

Question 4

Electromagnetic waves have

A. particle like properties
B. wavelike properties
C. both particle like and wavelike properties

D. neither particle like nor wavelike properties

Answer 4

C. both particle like and wavelike properties

Question 5

Emission of electrons when electromagnetic radiation falls on an object is

Answer 5

photoelectric effect

Question 6

What is the Heisenberg Uncertainty Principal state?

Answer 6

The Heisenberg Uncertainty Principal says that it is impossible to measure precisely both the position and momentum of a particle at the same time.

Question 7

An atom in ____ is an atom with the smallest allowable amount of energy.

Answer 7

a ground state

Question 8

What does EMR stand for?

Answer 8

Electromagnetic Radiation

Question 9

What is an EMR consist of?

Answer 9

Consists of oscillating perpendicular electric and magnetic fields moving simultaneously through space as waves.

Question 10

What are the properties of waves?

Answer 10

Frequency: number of cycles it undergoes per second
Wavelength: the distance the wave travels during one cycle
Speed; distance the wave moves per unit time (for EMR this would be the speed of light “c”)

Question 11

nm = m?
pm = m?
A = m?

Answer 11

nm = 10^-9 m
pm = 10^-12 m 
A = 10^-10 m

Question 12

What is the relationship between wavelength and frequency? and what does this mean for energy?

Answer 12

As wavelength increases, frequency decreases and vice versa. Energy is directly proportional to frequency, so if frequency is decreasing then so is energy.

As wavelength decreases, frequency increases and so does energy.

Question 13

What are the different EMR’s and which describe wave properties and energy within them?

Answer 13

RMIVUXG

RADIO MICROWAVE IN-FARED VISIBLE LIGHT ULTRA-VIOLET X-RAY GAMMA RAYS

The end near the radio waves has a higher wavelength, lower frequency, and not much energy. Whilst the end near the gamma rays has a lower wavelength, higher frequency, and higher energy.

Question 14

What is the amplitude and how does it affect brightness?

Answer 14

The amplitude is the height of the waves or troughs from the x axis and represents the intensity or the brightness of the light.

HIGHER AMPLITUDE = MORE INTENSE/BRIGHTER
LOWER AMPLITUDE = LESS INTENSE/DIM

Question 15

Define “continuum of radiant energy”.

Answer 15

Continuum of kinetic energy describes how each specific type of EMR meets the next. A continuum of the EMR’s as they connect with each other (as displayed in the spectrum).

Question 16

What part of the electromagnetic spectrum can humans see with their eyes?

Answer 16

The visible nature which ranges from 700nm to 400nm.
Where red is near 700nm and violet is near 400nm.
A way to remember the colours if to use the name of the EMR’S beside visible light.

Question 17

What is the difference between monochromatic and poly-chromatic light?

Answer 17

Monochromatic light refers to light of a single wavelength whilst poly-chromatic refers to light of many wavelengths.

Question 18

Is white light poly-chromatic?

Answer 18

Yes, white light is poly-chromatic as it contains many different wavelengths of light.

Question 19

What is refraction?

Answer 19

When a wave travels at through a different medium at any angle other than 90 degrees. The waves speed changes causing a change in direction called REFRACTION.

Question 20

What is dispersion and what is it related to?

Answer 20

Dispersion relates to refraction and is defined as to when white light separates (disperses) into its component colours when it passes through a refracting object. This occurs because each wave is refracted at a slightly different angle.

Question 21

What is diffraction?

Answer 21

Diffraction is when a wave strikes the edge on a object or passes through a slit as wide as it’s wavelength. In doing so, the wave has a tendency to bend around or create semicircular waves on the other side past the object.

Question 22

What is interference and what is it related to?

Answer 22

Interference is related to diffraction and arises the problem of DOUBLE SLITS. In this situation the nearby emerging waves interact through the process of interference.
CONSTRUCTIVE: the crests and trough match up in phase, and results in an addition of AMPLITUDE
DESTRUCTIVE: the crests meet at troughs and out of phase which results in the subtraction of the AMPLITUDE.

Question 23

What is a black body?

Answer 23

A black body is an idealized physical body that absorbs all incident electromagnetic radiation, regardless of frequency or angle of incidence. (It does not only absorb radiation, but can also emit radiation)

Question 24

What is the concept of black body radiation?

Answer 24

Black body radiation tries to create the concept that as a black body solid object is heated it begins to emit visible light. As it is heated to higher temperatures it begins to emit light at different colors because of the changes in wavelength and intensity (this is described as the characteristics of black body radiation).

Question 25

What is the double slit experiment?

Answer 25

The double-slit experiment in quantum mechanics is an experiment devised by physicist Thomas Young. It shows that light has both a wave nature or characteristic and a particle nature or characteristic, and that these natures are inseparable. … The same is true of electrons and other quantum particles.

Question 26

How does the black body radiation relate to quantized energy? What did Planck hypothesize?

Answer 26

Max Planck and other scientists developed the quantum theory to explain the black body radiation (to explain the BBR he created the formula E=nh(frequency).

Since black body radiation can only emit certain colors at certain temperatures, Planck hypothesized that the black body could only emit CERTAIN QUANTITIES OF ENERGY. A black body like any other object is made out of atoms, which means that the atoms as they change color –> wavelength –> frequency –> energy are emitting only certain quantities of energy.

THEREFORE, THEY ENERGY OF AN ATOM IS QUANTIZED (occurs in fixed positions).

Question 27

What is a quantum?

Answer 27

A quantum is a packet of energy.

FORMULA = (frequency)(n)

Question 28

When energy change occur in an atom?

Answer 28

An atom changes in energy by absorbing or emitting one or more packets of energy (quanta)

Question 29

What is the smallest allowed energy change in an atom?

Answer 29

Since, atoms emit/absorb energy by quantum packets the smallest allowed change in n=1.

Question 30

Who came up with the black body radiation?

Answer 30

Max Planck

Question 31

Who came up with the photoelectric effect?

Answer 31

Albert Einstein

Question 32

What is the photoelectric effect?

Answer 32

The photoelectric effect is when MONOCHROMATIC LIGHT of a sufficient frequency sines on a metal plate, causing a current to flow.