The Atom

• What is an atom?


  The stuff all elements and compounds are made of
• What are atoms made up of?

  Electrons

  Neutrons

  Protons
• Electrons


  Have a -1 charge

  Have orbitals

  Orbitals take up most volume in atom
• Nucleus


  Most of the mass is here

  Diameter is small

  Find protons and neutrons
• What is the relative mass of a proton?

  1
• What is the charge of a proton?

  +1
• What is the relative mass of a neutron?

  1
• What is the charge of a neutron?

  0
• What is the relative mass of an electron?

  1/1836
• What is the charge of a electron?

  -1
• What are the 2 nucleur symbols?

  Mass number

  Atomic number
• Mass number?


  Total number of protons and neutrons
• Atomic number?


  Number of protons

  All atoms = Same element = same number of protons
• What is an ion?


  An atom that has different numbers of protons and neutrons hence a + or - charge or - charge
• What does a - ion mean?

  More electrons than neutrons
• What does a + ion mean?

  Less electrons than protons

  Mg = 12 electrons

  Mg2+ = 10 electrons
• What is an isotope?

  Atoms with the same number of protons but a different number of neutrons
• What does the number and arrangement of electrons decide?

  The chemical properties
• Isotopes have the same electron configuration meaning...


  Same chem properties
• What do isotopes have different?

  Physical properties as they tend to rely on the mass of the atom