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Isotopes and Nuclear Radiation

Isotopes are different forms of the same element

  • All atoms of each element have a set number of protons. The number of protons in an atoms is its atomic number

  • The mass number is the number of protons+neutrons

  • Isotopes are atoms with same number of protons different number of neutrons

  • All elements have different isotopes, but there are usually only one or two stable ones

  • The other unstable isotopes tend to decay into other elements and give out radiation as they try to become more stable. This process is called radioactive decay

  • Radioactive substances spit out one or more types of ionising radiation from their nucleus-the ones you need to know are alpha, beta and gamma radiation

  • They can also release neutrons when they decay, as they rebalance their atomic and mass numbers

  • Ionising radiation is radiation that knocks electrons off atoms, creating positive ions, The ionising power of a radiation source is how easily it can do this

Alpha particles are helium nuclei

  • Alpha radiation is when an alpha particle is emitted from the nucleus. A a-particle is two neutrons and two protons

  • They don’t penetrate very far into materials and are stopped quickly-they can only travel a few cm in air and are absorbed by a sheet of paper

  • Because of their size they are strongly ionising

Beta particles are high-speed electrons

  • A beta particles, is simply a fast-moving electron released by the nucleus. Beta particles have virtually no mass and a charge of -1

  • They are moderately ionising. They penetrate moderately far into materials before colliding and have a range in air of a few meters. They are absorbed by a sheet of aluminium

  • For every beta particle emitted, a neutron in the nucleus has turned into a proton

Gamma rays are EM waves with a short wavelength

  • Gamma rays are waves of electromagnetic radiation released by the nucleus

  • They penetrate far into materials without being stopped and will travel a long distance through air

  • This means they are weakly ionising because they tend to pass through rather than collide with atoms. Eventually they hit something and do damage

  • They can be absorbed by thick sheets of lead or metres of concrete

Isotopes and Nuclear Radiation

Isotopes are different forms of the same element

  • All atoms of each element have a set number of protons. The number of protons in an atoms is its atomic number

  • The mass number is the number of protons+neutrons

  • Isotopes are atoms with same number of protons different number of neutrons

  • All elements have different isotopes, but there are usually only one or two stable ones

  • The other unstable isotopes tend to decay into other elements and give out radiation as they try to become more stable. This process is called radioactive decay

  • Radioactive substances spit out one or more types of ionising radiation from their nucleus-the ones you need to know are alpha, beta and gamma radiation

  • They can also release neutrons when they decay, as they rebalance their atomic and mass numbers

  • Ionising radiation is radiation that knocks electrons off atoms, creating positive ions, The ionising power of a radiation source is how easily it can do this

Alpha particles are helium nuclei

  • Alpha radiation is when an alpha particle is emitted from the nucleus. A a-particle is two neutrons and two protons

  • They don’t penetrate very far into materials and are stopped quickly-they can only travel a few cm in air and are absorbed by a sheet of paper

  • Because of their size they are strongly ionising

Beta particles are high-speed electrons

  • A beta particles, is simply a fast-moving electron released by the nucleus. Beta particles have virtually no mass and a charge of -1

  • They are moderately ionising. They penetrate moderately far into materials before colliding and have a range in air of a few meters. They are absorbed by a sheet of aluminium

  • For every beta particle emitted, a neutron in the nucleus has turned into a proton

Gamma rays are EM waves with a short wavelength

  • Gamma rays are waves of electromagnetic radiation released by the nucleus

  • They penetrate far into materials without being stopped and will travel a long distance through air

  • This means they are weakly ionising because they tend to pass through rather than collide with atoms. Eventually they hit something and do damage

  • They can be absorbed by thick sheets of lead or metres of concrete