Ouhsc Physics Exam 3

Front 1

The K-shell can hold a max of ____ electrons

Back 1

2

Front 2

The L-shell can hold a max of ____ electrons

Back 2

8

Front 3

The M-shell can hold a max of ____ electrons

Back 3

18

Front 4

This is the interaction between the positive and negative charges that keeps the electrons constantly attracted to the atoms nucleus

Back 4

Binding energy

Front 5

Which electron shell has the highest binding energy

Back 5

K (or whichever is closest to the nucleus)

Front 6

When describing the binding energy, it is depicted by a ________

Back 6

negative sign

Front 7

What does the binding energy tell us

Back 7

In order to completely remove an electron from the atom you would need that much energy

Front 8

If the BE of the K shell was -13.5eV and the BE of the L shell was -3.4eV. How much energy would it take to move an electron from the K shell to the L shell

Back 8

BE L shell - BE Kshell=
-3.4 - (-13.5)=

10.1 eV

Front 9

When we say that each particle has a charge, we mean that each unit of charge is equal to ______

Back 9

1.6 x 10E-19 coulombs

Front 10

What is the charge of a proton

Back 10

+1.6 x 10E-19 coulombs

Front 11

What is the charge of an electron

Back 11

-1.6 x 10E-19 coulombs

Front 12

What is the SI unit for energy

Back 12

joule

Front 13

What is the British system unit for energy

Back 13

erg

Front 14

What are the 3 units of energy we will be using in this course

Back 14

joule
erg
eV

Front 15

1eV = how many joules

Back 15

1eV= 1.6 x 10E-19 joules

Front 16

1eV = how many ergs

Back 16

1eV= 1.6 x 10E-12 ergs

Front 17

How much energy would we need to add to remove an electron from an atom completely

Back 17

the binding energy of the shell it is on

Front 18

T/F

All electrons in an electron shell have the same binding energy

Back 18

False
there are slight variations

Front 19

What determines the chemical properties of an atom

Back 19

the electronic configuration

Front 20

What determines the stability on an atom

Back 20

the nuclear configuration

Front 21

What term goes hand in hand with the term stability

Back 21

radioactivity

Front 22

If an atom is stable it is_______
If an atom is unstable it is ________

Back 22

stable = not radioactive

unstable = radioactive

Front 23

The mass of a proton and the mass of a neutron are almost the same, but the ______ actually has a greater mass

Back 23

neutron

Front 24

The atomic mass unit (amu) is a way for us to discuss the......

Back 24

mass of an atom

Front 25

1 amu is equal to........

Back 25

1 amu = 1/12 of the mass of a carbon 12 atom =
1.66 x 10^-27 kg

Front 26

A carbon 12 atom is equal to how many kilograms

Back 26

1.6605x10E-27 kg

Front 27

A nuclide is a _________

Back 27

nuclear configuration

Front 28

If a nuclide is unstable it is _____ and is refered to an a _______

Back 28

radioactive
radionuclide

Front 29

The atomic number is abbreviated by the what letter

Back 29

Z

Front 30

The mass number is abbreviated by what letter

Back 30

A

Front 31

The atomic number represents the.......

Back 31

number of protons in the nucleus

Front 32

The mass number represents the........

Back 32

number of protons and neutrons in the nuclues

Front 33

If an atom has 1 proton and 1 neutron what is its atomic number.
What is its mass number

Back 33

Atomic number of 1

Mass number of 2

Front 34

A carbon 12 atom has how many protons and how many neutrons. How can we figure this out. What is the atomic number?

Back 34

The 12 is the mass number, so we know it has 6 protons and 6 neutrons

Atomic number is 6 (all carbon has 6 protons)

Front 35

What is the mass number of Tecnesium 99

Back 35

99 (duh)

Front 36

What does the term nucleon describe.

Back 36

The number of particles (protons and neutrons) in the nucleus

Front 37

Tridium has a mass number of 3 and an atomic number of 1. Is it stable? Is it radioactive?

Back 37

unstable
radioactive

We know this because we can see it has a mass number of 3 and an atomic number of 1. So it has 3 particles in its nucleus, and one of them is a proton. This atom is unstable so it is radioactive

Front 38

Deterium has a mass number of 2 and an atomic number of 1. Is it stable? Is it radioactive?

Back 38

stable
not radioactive

We know this because we can see it has a mass number of 2 and an atomic number of 1. So it has 2 particles in its nucleus, and one of them is a proton. This atom is stable so it is not radioactive

Front 39

Define an isotope.

Back 39

any two or more forms of a chemical element, having the same number of protons in the nucleus, or the same atomic number, but having different numbers of neutrons in the nucleus, or different atomic numbers.

Front 40

Since like charges repel each other, what keeps the nucleus from splitting apart

Back 40

the strong nuclear force

Front 41

The ______ is the force that is trying to push the particles in the nucleus apart and the _______ is the force that hold the nucleus together.

Back 41

electrostatic force

strong nuclear force

Front 42

The strong nuclear force is _____ times stronger than the electrostatic force

Back 42

100

Front 43

How many atomic mass units make up a carbon 12 aotm

Back 43

12 amu

Front 44

Break down and weigh each particle of a carbon 12 atom

With this, explain the mass defect

Back 44

We can see that a carbon 12 atom has 6 protons, 6 neutrons, and 6 electrons. So....
We multiply each by the amu for each....

Pro 6 (1.007276) = 6.04366
Neu 6 (1.008665) = 6.05199
Ele 6 (.000549) = 0.00329

If you add all these up to total 12.09894 amu, you can see the mass of all the particles (when weighed seperatly) is actually more than the weight of the atom. This describes the mass defect. If you take the total weight of the atoms and subtract the mass number you get the mass defect

12.09894 amu - 12 = .09894amu
So a carbon 12 atom has a mass defect of .09894 amu

Front 45

What is the atomic mass unit of a proton

Back 45

1.007276 amu

Front 46

What is the atomic mass unit of a neutron

Back 46

1.008665 amu

Front 47

What is the atomic mass unit of a electron

Back 47

.000549 amu

Front 48

Define the mass defect

Back 48

When the mass of the parts weighs more than the entire atom.

Front 49

The mass defect represents the.......

Back 49

amount of energy that has to be applied to the nucleus to seperate the protons and neutrons (aka, the amount of force that needs to be applied to overcome the strong nuclear force)

Front 50

The nuclear binding energy is derived from the.....

Back 50

mass defect

Front 51

What is the relationship between mass and energy

Back 51

E=mc^2

Front 52

In the formula E=mc^2
what does the E represent
what does the m represent
what does the c represent

Back 52

E = energy in joules
m = mass in kg
c = velocity of light in a vacuum

Front 53

What is the velocity of light

Back 53

2.998 x 10^8 m/s
or
3 x 10^8 m/s

Front 54

We typically measure the mass of an atom in _____

Back 54

atomic mass units (amu)

Front 55

1 amu equals.......

Back 55

1/12 of a carbon 12 atom

Front 56

So we know that 1 amu = 1.66 x 10 ^-27 kg.

So what is the energy in joules of 1 amu

What is the energy of 1 amu in MeV

Back 56

E = mc^2
E = (1.66x10^-27kg)(3x10^8m/s)^2
(make sure to square both units)
E = 1.492x10^-10 kg m^2/s^2
(aka E = 1.492 x 10 ^-10 J)
This can be further converted to MeV by using more dimensional analysis with 1MeV = 1.602x10^-13 J

So 1.49 x 10^-10 J = 931 MeV

(so to cut all the bull shit 1 amu = 931 MeV)

Front 57

1 amu equals how many electron volts

Back 57

see very end of notes on 9-30-11. Its too many numbers with too much suprascript and dimentional analysis to put on here and im too lazy

answer is 931 x 10^6 eV

Front 58

The nuclear binding energy of a carbon 12 atom is _____MeV

Back 58

92 MeV

Front 59

Alpha particle has __ protons and __ neutrons and is essentially the same as _____ without its electrons

Back 59

2
2
helium

Front 60

Taking something with a lower mass and making it have a larger mass number describes fission or fusion

Back 60

Fusion

Front 61

Taking atoms with a higher mass and bringing them back to a smaller mass by breaking them apart,describes fission or fusion

Back 61

Fission

Front 62

Which is used more frequently, fission or fusion

Back 62

fission

Front 63

So every time an atom splits (fission) how much energy is released

Back 63

200 MeV of energy

Front 64

Describe what happens in fission

Back 64

We have an atom such as uranium-235 in a nuclear reactor, and we introduce a neutron. The neutron is absorbed into the uranium and we end up with uranium-236 which is fissionable. The uranium-236 breaks apart, and every time it breaks apart we get different types of atoms, and we get somewhere close to 200 MeV of energy that is relased. When it is released the energy heats up water which turns into steam which turns a turbin and produces electricity.

Front 65

What are the 2 main problems with fission?

Back 65

-How to shut it down
-The fission products (such as the krypton and barium) are radioactive and many if them have long half lives. These are not useful and cant be converted into fuel, so they are nuclear waste.

Front 66

Fusion produces about ______ of energy

Back 66

5.4MeV

Front 67

Fission produces about ______ of energy

Back 67

200 MeV

Front 68

Whats the problem with fusion?

Back 68

To make fusion happen we need huge amount of energy to fuse the atoms wioth the protons. So much that it takes more energy to make it happen then the end result. So we actually lose energy.

Front 69

So why is fusion better than fission?

Back 69

Because we don’t end up with nuclear waste

Front 70

Why do we use fission instead of fusion?

Back 70

It takes more energy to make a fusion reaction happen then the resulting energy. It’s a losing process.

Front 71

The sun is an example of fission or fusion?

Back 71

Fusion

Front 72

A hydrogen bomb is an example of fission or fusion?

Back 72

Fission creates the heat to cause the fusion to occur.

Front 73

The term “iso” means _______

Back 73

same

Front 74

__________ have the same number of protons and different number of neutrons

Back 74

Isotopes

Front 75

The Z number is the same and the A number is different in an iso_______

Back 75

isotope

Front 76

A ______ has the same atomic number and different mass number

Back 76

isotope

Front 77

________ have the same number of neutrons and different number of protons

Back 77

Isotones

Front 78

The Z number is different and the A number is different in an iso________

Back 78

isotone

Front 79

A _____ has a different atomic number and a different mass number

Back 79

isotone

Front 80

_________ have different number of protons and a different number of neutrons, but the mass number is the same

Back 80

Isobars

Front 81

The Z number is different and the A number is the same in an iso_______

Back 81

Isobar

Front 82

A _____has a different atomic number and the same mass number

Back 82

isobar

Front 83

_______ have the same number of protons and the same number of neutrons

Back 83

Isomers

Front 84

There are the same Z number and the same A number in an iso______

Back 84

isomer

Front 85

_____ has the same atomic number and same mass number

Back 85

isomer

Front 86

Sulfur, chlorine, and argon all have 20 neutrons, and different numbners of protons. Does this describe an isotpoe, isotone, isobar, or an isomer

Back 86

isotone

Front 87

Hydrogen-3 has 1 proton and 2 neutrons, helium-3 has 2 protons and 1 neutrons, but the mass number is the same. Does this describe an isotpoe, isotone, isobar, or an isomer

Back 87

isobar

Front 88

technesium- 99 and technesium-99m are an example of an isotpoe, isotone, isobar, or an isomer

Back 88

isomer

Front 89

technesium-99m decays to a metastable state where the number of ______ and _______ are the same, the ______ number is also the same, but it still has excess energy which results in the emission of a _________

Back 89

protons
neutrons
mass
gamma ray

Front 90

if the mass number is the same they are _______

Back 90

isobars

Front 91

if the atomic number is the same they are ______

Back 91

isotopes

Front 92

if the number of neutrons is the same (mass number - atomic number) we know they are ______

Back 92

isotones

Front 93

if everything is the same in an atom (ie, protons, neutrons, etc) it is an ______

Back 93

isomer.

Front 94

An atom has an atomic number (Z#) of 1 and a mass number (A#) of 3
It is hydrogen-3 and is not stable (radioactive). What makes it radioactive? When it tries to reconfigure itself we will get a _______

Back 94

It is radioactive because the proton to neutron ratio is unbalanced and it will attempt to stabilize itself by reconfiguring. When it reconfigured, we would get out a beta particle

Front 95

With beta particles, the negative charge comes from the _____

Back 95

neutron, so that neutral charge in the nucleus is now positive

Front 96

An atom with one proton and two neutrons emits a beta particle. What is left in the nucleus

Back 96

two protons and one neutron

Front 97

What is disintegration.

Back 97

When a nuclide emits a charged particle from the nucleus

Front 98

The unit for radioactivity is

Back 98

disintegrations per unit time

dpm or dps

Front 99

Disintegrations per second is actually measuring how many......

Back 99

disintegrations are coming off a material per second

Front 100

Is counts per second (cps) a unit for radioactivity

Back 100

no

Front 101

The common unit for radioactivity is the

Back 101

Curie (Ci)

Front 102

The international unit for radioactivity is the

Back 102

Bequerel (Bq)

Front 103

1Ci = how many dps

Back 103

3.7 x 10^10 dps

Front 104

1 Bq = how many Curie

Back 104

1 Ci

Front 105

1 Ci = how many Bequerel

Back 105

3.7 x 10^10 Bq

Front 106

You can predict the number of atoms that will disintegrate in a unit of time. This is based on this constant called the _________

Back 106

decay constant

Front 107

What is the formula for the decay constant

Back 107

ƛ = 0.693
T½

Front 108

The ________ is the time it takes for 50% of the activity to decay.

Back 108

half life

Front 109

At one half life we end up with _______ of the activity.
At 2 half lives we end up with _____ of the activity.

Back 109

50%
25%

Front 110

If you increase ƛ the half life gets larger or smaller

Back 110

smaller

Front 111

What is the formula for activity

Back 111

A =ƛN

Front 112

activity is measured in _____

Back 112

dps

Front 113

ƛ =

Back 113

decay constant (0.693 / T ½)

Front 114

N =

Back 114

number of atoms

Front 115

So if we have 10^12 atoms and a half life of 1 year, what is the activity?
Give the answer in bequerel curie,and microcurie.

Back 115

2.1 X 10^4 Bq
5.68 x 10^-7 Ci
.568 uCi

Front 116

What is the formula for finding how much radioactivity is left after a certain amount of time?

Back 116

A= Ao E^(-ƛT)

Front 117

Ao=

Back 117

original activity

Front 118

ƛ =

Back 118

0.693 / (T½)

Front 119

t =

Back 119

elapsed time

Front 120

So if we have an original activity of 2 Ci with a half life of 2 hours and an elapsed time of 2 hours, what is the activity?

Back 120

1 Ci

Front 121

A= Ao E^(-ƛT)
If you have:
A = 5 Ci
Ao = 12 Ci
T ½ = 1 HR

Solve for elasped time

Back 121

1.25 hours

Front 122

Ao = 10 Ci
T½ = 1 hr
t = 5 hrs

Solve for activity

Back 122

34.65 Ci

Front 123

Thsi is essentially a helium nucleus without the electrons

Back 123

alpha particle

Front 124

______emission occurs when the neutron to proton ration is too low

Back 124

alpha

Front 125

What does Q represent

Back 125

total energy release

Front 126

Every alpha particle results in a reduction of 2 in the ________.

Back 126

atomic number
We always lose 2 protons b/c an alpha particle has 2 protons

Front 127

In the case of alpha particles, how do we get total energy released of Q.

Is Q the energy of the alpha particle?

What do we need to take into account?

Back 127

Q = Mp – Md - M∝ - 2Me-

No

Recoil

Front 128

If you have Q = 0.0058amu, find the total energy released

Back 128

multiply it by 931 MeV

it equals 5.4 MeV

Front 129

Which particles are large enough that when they come off of the atom they produce some recoil

Back 129

alpha

Front 130

recoil particles push off of the parent of daughter

Back 130

daughter

Front 131

_______particles are essentially monoenergetic for a specific radionuclide

Back 131

Alpha

Front 132

are we concerned with recoil in beta particles

Back 132

Beta particles are so small that the daughter atom is not going to recoil, so with beta particles we are not worried about recoil

Front 133

The lowest mass beta emitter is ______

Back 133

tritium (hydrogen 3).

Front 134

_______particles are not monoenergetic

Back 134

Beta

Front 135

These have infinity small mass, has no charge, has no biological effects, can pass through without damage to tissue.

Back 135

antineutrino

Front 136

What are the two things that exist when we get total energy release of Q (Q is divided into these two things)

Back 136

beta and antineutrino