C1

• Mixtures can be separated using various methods:

  • Chromatography: to separate out mixtures
  • Filtration: to separate solids from liquids
  • Distillation: to separate mixtures of liquids
  • Crystallisation: to separate a soluble salt from a solution
• Evaporation is a quick method to separate a soluble salt from a solution
• Balancing symbol equations is essential to ensure the same number of atoms on both sides of the equation
• Atoms consist of protons and neutrons in the nucleus, with electrons moving around the nucleus in electron shells
• An ion is a charged particle that does not have an equal number of protons to electrons
• Isotopes are elements with the same number of protons but a different number of neutrons, resulting in different mass numbers
• Compounds are formed when two or more elements are chemically joined, held together by chemical bonds
• The periodic table organizes elements by atomic mass/proton number, showing where metals and non-metals are located
• Alkali metals are group 1 elements that are soft, very reactive metals with one electron in their outer shell
• Halogens are non-metals that become less reactive as you go down the group, with higher melting and boiling points
• Noble gases are un-reactive group 0 elements with full outer shells, making them very stable
• Transition metals are found between groups 2 and 3 in the middle of the periodic table, exhibiting properties like being strong, shiny, and good conductors of electricity and heat