This is a paper 2 separate science fact
- Group 1 elements get more reactive, or more unstable as you go down the group.
- Group 1 elements need to lose one electron to react
- Electrons are held in place by the protons in the nucleus
- The closer the nucleus is to the electron, the stronger the force will be
- Therefore, the further away the nucleus is to the electrons, the weaker the force keeping them together will be.
- Bigger atoms (the ones with more shells, lower down in the group) will have their last shells very far away from the nucleus
- This means the electron will be lost easier
- Therefore it reacts more easily/quickly/vigorously
- Smaller atoms (higher in the group) are less reactive as it takes much less energy to break the force.