Characteristics and Structure of Matter

Question 1

Where is radiation created and then later absorbed within?

Answer 1

Some material substance or matter

Question 2

Where does radiation interaction occur (both formation and absorption)?

Answer 2

within individual atoms

Question 3

What are the two major regions of atoms?

Answer 3

1. Nucleus

2. Electron shells

Question 4

What is the nucleus a source of?

Answer 4

Source of energy for the radiation used in nuclear medicine procedures

Question 5

What is the nucleus involved in?

Answer 5

Production of x-ray photons

Question 6

How is radiation absorbed?

Answer 6

Interacting with electrons located in the shells surrounding the nucleus

Question 7

How is one form of x-radiation produced?

Answer 7

Transition in the shell electrons

Question 8

What is the conventional model of atoms consisting of nucleus?

Answer 8

protons and neutrons surrounded by electrons located in specific orbitals or shells

Question 9

How is the nucleus shown?

Answer 9

A ball or cluster of particles at the centre of atom

Question 10

What is quite small in comparison to the total dimension of atom?

Answer 10

Nucleus

Question 11

What is contained within the nucleus?

Answer 11

Most of mass of atom

Question 12

What is located at a much greater distance from the nucleus?

Answer 12

Electrons

Question 13

What are two basic particles of nuclei?

Answer 13

1. Neutrons

2. Protons

Question 14

What is almost the same size but differ in their electrical charge?

Answer 14

1. Neutrons

2. Protons

Question 15

What has no electrical charge and contribute only mass to the nucleus?

Answer 15

Neutrons

Question 16

What does proton have a positive charge equal in strength to?

Answer 16

Negative charge carried by an electron

Question 17

What relates to nuclei’s neutron-proton composition?

Answer 17

Physical and chemical characteristics of a substance

Question 18

What establishes the chemical identity of the atom?

Answer 18

The number of protons in a nucleus (atomic number [Z])

Question 19

What does each atomic number correspond to?

Answer 19

Different chemical element

Question 20

Why is not convenient to express the mass of nuclei and atomic particles in the conventional unit of kilograms?

Answer 20

Very small size

Question 21

What is the relationship between atomic mass unit and kilogram?

Answer 21

1 amu = 1.66 x 10-27 kg.

Question 22

What is difference in mass between a neutron and proton?

Answer 22

Quite small

approx 0.1%

Question 23

What is required to equal the mass of a proton or neutron?

Answer 23

More than 1,800 electrons

Question 24

What is the mass number (A)?

Answer 24

The total number of particles (neutrons and protons)

Question 25

What is proportional to the mass number?

Answer 25

The total mass or weight of a nucleus

Question 26

What happens when nucleus is formed?

Answer 26

Some of the mass is converted into energy

Question 27

What does lighter element contain?

Answer 27

Almost equal numbers of neutrons and protons

Question 28

What is the consequence of the size of the nucleus increasing?

Answer 28

The ratio of neutrons to protons increases to a maximum of about 1.3 neutrons per proton for material with very high atomic numbers

Question 29

How is the number of neutrons in a specific nucleus obtained?

Answer 29

Subtracting the atomic number from the mass number

Question 30

What can one chemical element have?

Answer 30

Nuclei containing different numbers of neutrons

Question 31

What determines if a nucleus is radioactive?

Answer 31

The variation in neutron composition

Question 32

How many different atomic numbers or elements are there?

Answer 32

106

Question 33

How many different neutron-proton combinations are now known?

Answer 33

at, least 1,300

Question 34

Define Isobars?

Answer 34

Nuclides having the same mass number but different atomic numbers

Question 35

What cannot belong to the same chemical element?

Answer 35

A pair of isobars

Question 36

Define isomers

Answer 36

Two nuclei that have the same composition but varying energy

Question 37

What will a nucleus in the metastable state give off?

Answer 37

Its excess energy and change to the other isomer

Question 38

Define Isotones

Answer 38

Nuclides that have the same number of neutrons

Question 39

What is the ability of a nucleus to emit radiation energy related to?

Answer 39

Level of stability

Question 40

What is nuclear stability determined by?

Answer 40

Balance of forces within the nucleus

Question 41

What is a significant factor that determines the balance between internal forces and therefore nuclear stability?

Answer 41

The ratio of number of neutrons to the number of protons

Question 42

When will the nucleus be generally radioactive?

Answer 42

If the neutron-proton ratio is slightly above or below the ratio for stability

Question 43

When does a nucleus emit energy?

Answer 43

When it changes to a more stable form

Question 44

What process creates energy?

Answer 44

The fusion of two small nuclei to form a larger nucleus

Question 45

How is radiation energy created?

Answer 45

When nuclei undergo spontaneous radioactive transitions to create more stable nuclear structures

Question 46

What will the mass of 1g completely converted produce?

Answer 46

25,000,000 kilowatt-hours

Question 47

What are clinical applications interested in?

Answer 47

Amount of energy released by an individual atom

Question 48

What is kiloelectron volts (keV)?

Answer 48

A relatively small unit of energy

Question 49

What is the relationship between some other energy units and keV?

Answer 49

1 erg = 6.24 x 108 keV 1 j = 107 erg = 6.24 x 1015 keV.

Question 50

What is the energy equivalent of one electron mass?

Answer 50

511 keV | referred to as the rest-mass energy of an electron

Question 51

What does orbital electrons become involved in?

Answer 51

Actual emission of energy from the atom

Question 52

Where are electrons located in?

Answer 52

orbits or shells in the space surrounding a nucleus

Question 53

What is the atomic number?

Answer 53

The number of electrons contained in a normal atom equal to the number of protons in the nucleus

Question 54

What does a shell have?

Answer 54

Limited electron capacity

Question 55

What is the maximum capacity of the K, L, M shells?

Answer 55

K - 2 L- 8 M-18

Question 56

How are electrons bound to the positive nucleus of an atom?

Answer 56

Negative electrical charge

Question 57

What is binding energy a form of?

Answer 57

Electron potential energy

Question 58

What is designated the zero point?

Answer 58

A location outside the atom where the electron is no longer under the influence of nucleus

Question 59

Which shell is closest to the nucleus?

Answer 59

K shell | Lowest energy level

Question 60

Define ionization

Answer 60

The removal of an electron from an atom

Question 61

What is considered ionizing radiation?

Answer 61

X-ray and gamma photons | sufficient energy to remove electrons from atoms

Question 62

What cannot produce ionization?

Answer 62

Visible light

Question 63

When are photons absorbed?

Answer 63

When they collide with electrons