Basics

Question 1

What is alpha decay and what type of nuclei does to occur to

Answer 1

Emission of a helium nucleus

Preferred mode for nuclei heavier than Pb with a p/n ratio along the valley of stability

Question 2

What is beta - decay and where is it preferred

Answer 2

Emission of an electron and an anti-neutrino

Preferred mode of decay for nuclei with excess of neutrons

n → p + e− + antineutrino (v bar)

Question 3

What is Beta plus decay and when is it preferred

Answer 3

Emission of a positron and a neutrino

Preferred mode of decay for nuclei with excess of protons

p → n + e+ + ν (neutrino)

Question 4

What’s the equation for electron capture

Answer 4

p + e− → n + ν

Question 5

Half life equation

Answer 5

T1/2 = ln2 / λ

λ is decay constant, the probability of decay per unit time

Half life is given in seconds

Question 6

Activity equation

Answer 6

Activity is the rate of decay therefore

A = λN

N is the number of atoms

Question 7

Mean lifetime equation

Answer 7

Number of atoms / rate of decay

N/ λN = 1/ λ

Question 8

Avogadro constant

Answer 8

6.022 x 10^23

Question 9

What is a disintegration

Answer 9

The emission of particle from a nucleus