Atomic Structure

Atomic Structure

1. Periodic table

   • The big number is the mass of the atom
     • The number of protons and neutrons added together in the nucleus
   • The smaller number is the amount of protons in the atom sometimes called the atomic number
     • This number also represents how many electrons are on the energy shells
     • To find the amount of neutrons you take away the atomic number from the mass

2. As you go down the groups the elements get more reactive because the outer electrons of the atom are further away from the nucleus

   • All atoms consist of electrons, protons and neutrons
     • Electrons are found on energy shells which surround the nucleus
     • Protons and neutrons are found in the nucleus

3. In each row the elements have the same amount of shells

   • Protons have a positive charge of +1
   • Neutrons have a neutral charge (0)
   • Electrons have a negative charge of -1

4. The elements in each group all have something in common, for example: in group 0 the elements all have a full outer shell

   • The group number corresponds to the amount of electrons on the outer shell.
   • The electronic structure is laid out like a list with commas, for example: neon is laid out like 2,8