When atoms gain/lose electrons, all they're trying to do is gain a full outer shell.
Metals lose electrons to form positive ions
Non-metals gain electrons to form negative ions
The number of electrons lost/gained is the same as the charge on the ion
Group 1 and 2
elements are
metals.
They lose electrons
to form positive
ions
Cations
Group 6 and 7
elements are non-
metals
They gain electrons
to form negative
ions
Anions
Group 1 elements form
1+ ions, because they
have 1 electron in their outer shell
Group 2 elements form 2+
ions, because they have
2 electrons in their outer shell
Group 6 elements from 2-
ions
Group 7 elements form
1- ions
As you go down each group, you add electron
shells, so the outer electrons get further from the nucleus
As you do down, the outer electrons get further from
the nucleus
For Groups 1 and 2, this
means it gets easier to remove the outer electrons so its more reactive as you go down the group
For Groups 6 and 7, it gets harder for the nucleus to attract extra electrons to form ions, so the elements get less reactive as you go down the group.
When a metal and non metal react together, the metal loses electrons to form a positively charged ion and the non mental gain electrons to form a negatively charged ion
These oppositely charged ions are then strongly attracted to one another by electrostatic forces and from an ionic bond
They are held together by electrostatic froces
The oppositely charged particles
have to BALANCE
You can show Ionic bonding using Dot and Cross Diagrams