1st 20 elements

Cards (17)

  • The alkali metals have one electron in their outer shell, represented by the electron configuration 2s1 3s1 4s1.
  • Group seven elements, known as the halogens, have one electron missing in their outer shell, represented by the electron configuration 2s2 2p5.
  • Group three elements have an ionization state of +3.
  • Group zero elements, also known as the inert gases or noble gases, have a full set of electrons and are not particularly bothered about forming any compounds.
  • The ionization state can be used to determine the formula for compounds, for example, lithium oxide is Li2O and magnesium oxide is MgO.
  • Group two elements have an ionization state of +2.
  • Ionic compounds such as lithium, sodium, and potassium want to get rid of an electron, resulting in an ionization state of +1.
  • The first 20 elements are crucial for BTEC Applied Science, A-level Physics, and GCSE Chemistry.
  • Learning the first 20 elements can be challenging, but it's worth it as they make up 90% of what is needed to know.
  • Hydrogen, although it's not a metal, is officially in group one but is drawn on its own due to its unique properties.
  • The first 20 elements are arranged in groups one through seven, with hydrogen being a special case.
  • Metals and non-metals are typically arranged on the periodic table, with metals on the left and non-metals on the right, excluding hydrogen.
  • About three-quarters of elements are metals, with the non-metals typically being located in the top right hand corner.
  • The atomic number or proton number is the number of protons in the nucleus of a neutral atom.
  • The relative atomic mass and the atomic number are often confused, but they are different numbers.
  • Group one metals, also known as the alkali metals, include lithium, sodium, potassium, rubidium, cesium, and francium.
  • Group one metals, also known as the alkali metals, react with water.