Elements, isotopes and relative atomic mass

• Atom


  Made up of a central nucleus which comprises protons and neutrons, and electrons orbiting that nucleus
• Protons


  Determine which element the atom is
• Hydrogen


  • Smallest element, with 1 proton and 1 electron
• There are around 100 different elements
• Periodic table


  Organizes elements into boxes, each representing a different element
• Nuclear symbol


  The box representing an element in the periodic table
• Atomic number


  The number of protons in the nucleus of an atom, unique to each element
• Isotopes


  Different forms of the same element that have the same number of protons but a different number of neutrons
• Relative atomic mass


  The average mass of all the isotopes that make up a particular element
• Calculating relative atomic mass

  Multiply each isotope's abundance by its mass, sum these, then divide by the sum of the abundances of all the isotopes
• The relative atomic mass of copper is 63.6