Crossword

123456
Across
  1. 4. This particle has a relative mass of 1/1840
  2. 6. This is found in the centre of an atom
Down
  1. 1. This scientist ordered elements by atomic number
  2. 2. The vertical columns on the periodic table
  3. 3. The horizontal rows on the periodic table
  4. 5. This scientist carried out the gold foil experiment