Nuclear Chemistry

• Matter is anything that takes up space and has mass.
• Matter can be divided into pure substances and impure substances.
• Pure substances include elements (made up of one type of atom) and compounds.
• Compounds are made of two or more types of elements chemically joined together into particles that cannot be physically separated.
• A molecule is two or more atoms chemically bonded to each other (O2).
• Isotopes are atoms of the same element with the same number of protons but a different numbers of neutrons (Carbon-14, 6prot,8neut).
• Atoms that are unstable have either too many protons or too many neutrons.
• Radioisotopes are radioactive isotopes of an element - unstable atoms that break down and release electromagnetic energy from their nucleus.
• Half-life is the time taken for half of a radioactive material to decay.
• When a nucleus has too many protons, like charges repel and cause the nucleus to break down and release alpha particles (2prot,neut).
• A new element is also formed, one that has an atomic number two less than the original element.
• When a nucleus has too many neutrons, a neutron breaks down into a proton and an electron.
• The proton is retained and the electron is emitted as beta radiation.
• Atomic number increases by creating new element.
• Alpha particles ionise other atoms strongly (more charge).
• Alpha particles have low penetrating power as they lose energy when ionising.
• Beta particles ionise atoms as they pass through and are more likely to penetrate other atoms.
• Gamma rays are high-energy radiation and are more penetrating than alpha or beta radiation.
• Gamma rays are emitted when the protons and neutrons in an unstable nucleus rearrange and emit energy instead of a particle (no mass/charge).
• Nuclear fission: when a large nucleus splits into two small nuclei and releases a significant amount of energy.
• Nuclear fusion: When small nuclei are joined together to form a larger nucleus.
• Nuclear fusion releases far more energy than fission, occurs in stars.
• Nuclear energy can also be used to generate electricity instead of conventional methods that use fossil fuels.
• Nuclear power plants have low emissions of CO2 and SO2 gases and don't rely on coal, which is a nonrenewable resource.
• One of the main issues in the nuclear industry is nuclear waste.
• Nuclear waste contains radioactive elements such as plutonium, which has a half-life of 24 000 years.
• Workers handling such radioactive materials are exposed to dangerous ionising radiation, which causes cancer.
• Prolonged exposure to radiation damages living cells and can lead to diseases such as leukaemia and cancer.
• Radiation can also damage DNA and lead to birth defects.