Atoms

• What is the relative mass of a neutron ?

  1
• What is the charge of a proton ?

  Positive 1 or +1
• What is the relative mass of a proton ?

  1
• What is the charge of a neutron?

  Neutral or 0
• Overall charge of an atom

  Neutral or 0
• What is the charge of an electron ?

  Negative, or -1
• Why do atoms have a neutral charge ?

  Equal number of protons and electrons so the charges cancel out.
• What is the relative mass of an electron ?

  0 or 1/2000 or ‘negligible’
• How can you use the atomic number and mass number of a given atom, to work out how many neutrons it has ?

  mass number - atomic number
• What does the ‘mass number’ of an atom tell you ?

  Total number of protons + neutron the atom has
• What does an ‘atomic number‘ tell you ?

  Number of protons