Elements, isotopes

• What is an element?

  A substance made of only one type of atom
• How many elements are there?

  Approximately 100
• How can you represent elements?

  With symbols e.g: Fe = iron, C = carbon
• What is an isotope?

  Atoms of the same element with the same number of protons and electrons and a different number of neutrons.
• What is the abundance of an isotope?

  The % of atoms in a sample which are a particular isotope.
• What does relative atomic mass mean?

  Relative atomic mass is the average mass of all the isotopes of an element, taking into account the abundance and mass number of each isotope.
• How do you work out relative atomic mass?

  isotope abundance % x mass nom + isotope abundance % x mass nom divided by 100
• What does indivisible mean?

  Cannot be divided