fundamental

Question 1

What is the neutron number of mercury?​

​8​

80​

201​

121

Answer 1

201-80=121

Question 2

What is the definition of an isotope?​

a) Same proton number so same element, but different number of neutrons​

b) Same mass number but different atomic number​

c) Same number of neutrons but different number of protons​

d) the same number of protons and neutrons but they have different amounts of energy.​

Answer 2

A

Question 3

Which force is responsible for the transformation of a neutron in to a proton?​

Nuclear force​

Strong force​

Weak force​

Electromagnetic force

Answer 3

weak

Question 4

How many electrons are in the M shell?​

25​

16​

18​

36

Answer 4

ans: 18
m is the third shell
3 squared = 9
x2= 18
2(n^2)

Question 5

Using the diagram, how much energy is released when an electron moves from L–>K?​

11eV​

69eV​

2.8eV​

58eV

Answer 5

the difference between the two shells
58eV

Question 6

what is an isobar

Answer 6

equal A. Same mass number but different atomic number​

Question 7

what is an isotone

Answer 7

same N
Same number of neutrons but different number of protons

Question 8

what is an isomer

Answer 8

In atomic physics they have the same number of protons and neutrons but they have different amounts of energy. They are in a metastable state.

Question 9

nucleons and the nucleus are held together by which force?

Answer 9

strong force

Question 10

which radioactive decay modes are isobaric?

Answer 10

the mass stays the same: isomeric transition, positron emission (peta positive), beta negative, electron capture.

Question 11

which radioactive decay types cause transmutation

Answer 11

a different element is formed: alpha decay, beta neg, beta positive, electron capture (spontaneous fission)

Question 12

below a z number of 20, what is the stable ratio of protons and neutrons?

Answer 12

1:1

Question 13

above a z number of 20, what is a stable ratio of neutrons to protons?

Answer 13

1.5:1

Question 14

what is the equation for negatron decay?

Answer 14

too many neutrons

Question 15

what is the equation for alpha decay?

Answer 15

too many nucleons- very heavy

Question 16

what is the equation for electron capture?

Answer 16

p+e-= Neutron.
This competes with β+ decay as it also occurs in proton-rich nuclei. If the energy difference between the parent and daughter nuclides is too low for positron emission an inner shell electron is captured by the nucleus converting a proton into a neutron (i.e. positive + negative = neutral). As with β+ decay the mass number remains the same but the atomic number decreases by 1. This emission causes characteristic X-rays.

Question 17

what is the equation for beta positive decay?

Answer 17

too few neutrons. The extra proton decays into a neutron (which is retained in the nucleus), a positron (β+ or e) and an electron neutrino (ve). A neutron is gained, and a proton is lost meaning the mass number remains equal but the atomic number decreases by 1. This form of radioactivity, with the production of a positron, is important in PET imaging. The emitted positron travels only a minimal distance before it undergoes an annihilation reaction with the production of two 0.511 MeV photons that travel in opposite directions to one another.​

Question 18

what is isomeric transition?

Answer 18

A radionuclide in a metastable excited state decays to its ground state by isomeric transition and the number of protons and neutrons remain the same and the mass number and atomic number remain unchanged. Excess energy is emitted as gamma ray, internal conversion electron or both. Internal conversion is energy transfer to an orbital electron ejecting it. The ejected electron is called a conversion electron (E = gamma ray - binding E), often causes characteristic XR or Auger electron. ​e.g. technectium

Question 19

which decay produces gamma radiation?

Answer 19

isomeric transition

Question 20

1. What is the primary characteristic of alpha particles?​

A. High energy photons​
B. Heavy particles with a short range​
C. Light particles that can be subdivided into β+ and β-​
D. Electrically neutral particles with little mass

Answer 20

B

Question 21

2. Which of the following emissions occurs during β- decay?​

A. Helium atom​
B. Positron​
C. Electron and electron antineutrino​
D. Characteristic X-rays

Answer 21

C

Question 22

​

3. What process competes with β+ decay in proton-rich nuclei?​

A. Alpha decay​
B. Electron capture​
C. Isomeric transition​
D. Negatron decay

Answer 22

B

Question 23

​

5. What is emitted during isomeric transition?​

A. Alpha particles​
B. Helium atom​
C. Gamma rays or internal conversion electrons​
D. Positrons and neutrinos

Answer 23

C

Question 24

​

6. What is produced in positron decay that is significant for PET imaging?​

A. Characteristic X-rays​
B. Auger electrons​
C. Two 0.511 MeV photons​
D. A helium nucleus

Answer 24

C

Question 25

7. Which type of radioactive decay occurs when a neutron is converted into a proton?​

A. Beta-plus decay (β+)​
B. Beta-minus decay (β-)​
C. Alpha decay​
D. Electron capture

Answer 25

B

Question 26

8. What happens to the atomic number during electron capture?​

A. It increases by 1​
B. It decreases by 1​
C. It remains unchanged​
D. It increases by 2

Answer 26

B. a proton and electron become a neutron

Question 27

9. What type of emission results from energy transitions in the electron shell?​

A. Gamma rays​
B. Characteristic X-rays​
C. Neutrinos​
D. Beta particles​

Answer 27

B. gamma from nucleus, x rays fron electrons

Question 28

what is the unit of radioactivity

Answer 28

Unit of radioactivity: becquerel Bq.
1Bq= 1 disintegration/s
mBq= megabecquerel
sometimes curies (Ci) or millicuries
1mCi= 37MBq

Question 29

define specific activity

Answer 29

Definition: The rate at which a radionuclide decays per unit of mass
Units: Usually given in becquerels per kilogram (Bq/kg) or curies per gram (Ci/g)

Activity: the quantity of radioactive material, expressed as the number of radioactive atoms undergoing nuclear transformation per unit time (t) is called activity (A). Mathematically it is equal to the change (dN) in the total number of radioactive atoms (N) in a given time (dt)
Specific activity takes in to account the weight of the radioactive material.
λN multiplied by the weight. Therefore λNw.

Question 30

what is the decay constant?

Answer 30

The radioactive decay constant, represented by the symbol λ, is the probability that a nucleus of a radioactive nuclide will decay in a unit of time. The decay constant is a characteristic of unstable radionuclides, which spontaneously decay into a more stable configuration. each nuclide has its own constant.
Nuclear decay is a random unpredictable process. Observation of a larger number of atoms over a period of time allows an average rate of transformation (decay) to be established.
The number of atoms decaying per unit time is proportional to the number of unstable atoms (N) present at any given time:
dN/dt ∝N
This can be changed to equality by adding a constant
-dN/dt=λN–> activity.

Question 31

what is the radioactive half life?

Answer 31

Half-life is the time it takes for half of the unstable nuclei in a sample to decay or for the activity of the sample to halve or for the count rate to halve.
The number of radioactive atoms remaining in the sample and the number of elapsed half lives are related by the following equation:
N=N0/2n
Where N is the number of atoms remaining, N0 is the initial number of radioactive atoms, and n is the number of half lives that have elapsed.

Question 32

how are half life and the decay constant linked in an equation

Answer 32

Question 33

what is the definition of biological half life?

Answer 33

Biological Half-life is defined as the period of time required to reduce the amount of a drug in an organ or the body to exactly one half its original value due solely to biological elimination. tbiol is affected by many external factors. Perhaps the two most important are hepatic and renal function

Question 34

what is the effective half life? and how is it calculated?

Answer 34

A combination of nuclear and biological half lives to capture the effect of both.
Effective Half-Life is defined as the period of time required to reduce the radioactivity level of an internal organ or of the whole body to exactly one half its original value due to both elimination and decay. The teff can be measured directly. For example, one can hold a detection device 1 m from the patient’s chest and count the patient multiple times until the reading decreases to half of the initial reading. The patient is permitted to use the rest room between readings as needed, so both elimination and decay are taking place.

Question 35

continue from 1.4