Radioactivity Flashcards
Spontaneous Radiation is
The emission of radiation in a property of the substance and occurs naturally
Radiation was discovered by
Henri Becquerel in 1896 during a photographic experiment
Pierre and Marie Curie contribution
Used 8 tonnes of uranium .
Isolated two new elements called polonium and radium
received nobel prizes which Marie collected after Pierre died
Types of Radiation
Alpha particles 𝑎
Beta Particles B
Gamma radiation y
Radiation is
The spontaneous breaking down of unstable nuclei with the emission of one or more types of radiation
Alpha particles are
It is blocked by
Example
Used in
Groups of two protons and two neutrons stuck together
A sheet of paper
Americium 241
Smoke detectors
Beta Particles are
It is blocked by
Example
Used in
Formed when a neutron splits a proton and an electron and the electron is released
5mm of aluminium
carbon 14
Carbon dating
Gamma rays is
It is blocked by
Example
Used in
High energy electromagnetic radiation released by the unstable nucleus to expel access energy
A thick block of lead
Cobalt 60
Cancer treatment
Nuclear Reactions is
A process that alters the composition, structure or energy of an atomic nucleus
Loss of an alpha particle
When an atom losses an alpha particle it changes into an atom of the element two spaces below it on the periodic table. Mass number decreases by 4
e.g
Radium-226 = radon-222 + alpha particle
Loss of a beta particle
It changes into the atom of the element one place after it in the periodic table. Mass number remains the same.
e.g
C= N + e
Gamma example
No new atom of an element is formed, only energy is lost from the atom
Transmultation is
The transformation of one element to another
The Half Life is
The time taken for half of the nuclei in any given sample to decay
Simple Half Lives
Carbon-14=?
Cobalt-60=?
Polonium-234
5700 years
5 years
0.15 millisecond
