Radiation Physics Test 1

Bohr Model

model of the atom in which electrons move rapidly around the nucleus in paths called orbits

2n^2

How do u figure how many electrons r in each orbital shell?

Isotopes

elements that have the same number of protons but different number of neutrons

Isotones

elements having the same number of neutrons

Isobars

Elements with same mass number (A) but different atomic number (z)

Isomers

Elements with same A and Z but in a different nuclear state (metastable state)

Nuclear fusion

Combination of 2 lighter nuclei

Nuclear fission

Nucleus with atomic number greater than 56 splits into 2 smaller nuclei

Radioactive decay

When nature attempts to balance forces and spontaneous transformation of a nucleus into a lower binding energy

Gamma rays

What is given off when radioactive decay occurs?

Daughter

What is the new product called after radioactive decay and is more tightly bound (high BE)?

ratio of neutrons to protons

What is stability dependent on?

They r equal

What is the ratio of neutrons to protons for low atomic numbers?

More neutrons than protons

What is the ratio of neutrons to protons for high atomic number elements?

Protons

Too many of what makes the nucleus unstable?

1.4 neutrons for 1 proton

What is the rule of thumb for balance with neutrons and protons?

Annihilation reaction

When positron meets electron, they disappear, what is this?

e-, B-, beta negative with -1 proton count

What are the symbols for electron?

e+, B+, beta positive with +1 proton count

What are the symbols for positron?

P, 1/1 H

What are the symbols for proton?

N, 1/0 n

What are the symbols for neutron?

d, 2/1 H

What are the symbols for deuteron?

4/2 He, a

What are the symbols for alpha particles?

Joule

What is the basic unit of energy?

100

How many centigrays are in a gray?

100

How many Rads are 1 gray?

Radioactivity

Phenomenon where radiation is given off in the form of particles or electromagnet waves. Atom is attempting to become stable and discovered by Becquerel

Nucleus

Where do gamma rays originate from?

Inverse of the decay constant than equals 1.44 (1/2 life)

What is the formula for mean or average life a radioactive atom?

High atomic numbers (Z>82)

When is alpha decay most frequent?

Positron or negatron

Beta decay process involves ejection of what?

Excess neutrons (high n/p) ratio and must be reduced. Neutron is turned into a proton with a negatron

What usually is the reason for negatron emission?

Deficiency in neutrons (low n/p) ratio. Proton turned into a neutron and positron

What usually is the reason for positron emission?

Orbital electron gets captured by nucleus and combines with a proton, transforming into a neutron

What is electron capture?

Electron capture

What is an alternative to positron decay?

Electron capture

What decay gives off characteristic electrons?

Transient equilibrium

When half life of parent is not much longer than the daughter

Secular Equilibrium

When half life of parent is much longer than the daughter

Deuteron bombardment

What nuclear reaction is called stripping?

Photodisintegration

A high energy photon hits a nucleus and emits a nucleon but most of the time it emits a neutron

3 x 10^8 m/s

Speed of light

6.62 x 10^-34 J-sec

Planck's constant

c = λv

What formula helps you find wavelength or frequency?

E = hv

What formula helps you find energy or frequency?

1626 years

What is radium 226 half life?

3.83 days

What is radon 222 half life?

30 years

What is cesium 137 half life?

73.8 days?

What is iridium 192 half life?

5.26 years

What is cobalt 60 half life?

59.6 days

What is iodine 125 half life?

2.7 days

What is gold 198 half life?

8.06 days

What is iodine 131 half life?

17 days

What is palladium 103 half life?