1. Rutherford’s alpha scattering experiment. source of alpha particles thin gold foil photographic film beam of  particles most pass straight through 1 in 20 000 deflected

2. Rutherford’s explanation. atoms of gold in gold foil Path of an  particle nucleus of gold atom All these  particles pass straight through the empty space that makes up most of the atom. This  particle passes close enough to nucleus to be repelled As  particles are positively charged, the nucleus must contain positively charged protons.

3. atoms of gold in gold foil nucleus of gold atom As only 1 in every 20 000  particles are repelled the nucleus must be very small. Size of the nucleus.

4. Rutherford’s model of the atom. Tiny nucleus containing the positively charged protons. Rest of atom is mostly empty space. The negatively charged electrons are spinning round the nucleus.