Radioactivity Flashcards
What is radioactivity?
Radioactivity is the spontaneous decay of an unstable atomic nuclei by the emission of ionizing radiation and the production of energy.
What are the types of ionizing radiation?
Alpha particles (4:2He)
Beta particles (0:-1β)
Gamma rays (0:0γ)
What is the nature of alpha particles?
They have helium nuclei (4:2He)
What is the charge of an alpha particle?
2e = 2(+1.6×10^-19 C)
What is the mass of alpha particles?
6.65×10^-27 kg
What is the effect of magnetic field on an alpha particle?
It is slightly deflected towards the south pole (“slight” because of its larger mass).
What is the penetrating power of alpha particles?
It is the least of the three; a sheet of paper can stop it.
What is the nature of beta particles?
They are high energy electrons produced from the nucleus of an atom.
What is the charge of beta particles?
They have a charge of -e = -1.6×10^-19 C
What is the mass of beta particles?
They have a mass of 9.11×10^-31 kg.
What effect does magnetic field have on beta particles?
Beta particles are deflected towards the north pole. They have higher deflection due to their smaller mass (compared with alpha particles)
What is the penetrating power of beta particles?
Beta particles have medium level penetrating power; they can be stopped by several millimetres of aluminium foil.
What is the nature of gamma rays?
They are electromagnetic waves with short wavelengths (and high frequency).
What is the charge of gamma rays?
They have no charge.
What is the mass of gamma rays in kg?
They have negligible mass.
What is the effect of magnetic field on gamma rays?
Magnetic field has no effect.
What is the penetrating power of gamma rays?
Highest penetrating power (lowest ionizing energy) of the three; can only be stopped by several centimetres of lead.
What is transmutation?
Transmutation is the process of the changing of one element into another through ionizing radiation.
What is binding energy?
Binding energy is the total energy needed to completely pull apart the nucleons in the nucleus of an atom.
What is the binding energy per nucleon?
Binding energy per nucleon is the average energy required to separate a single nucleon from an atom’s nucleus.
What is a (fission) chain reaction?
This is a set up where the neutrons generated by a fission reaction prompts the further splitting of other unstable nuclides, cumulating intp a long series of fission reactions.
What is nuclear transmutation?
Nuclear transmutation is the process of transforming one nuclide (that is, the nucleus of a particular atom) into another either by the natural decay of the nuclide, or artificial decay by bombarding it with ionizing radiation.
What is 1amu equivalent to?
1amu = 1.66 × 10-27kg
