The periodic table

Mendeleev’s work

Grouped the elements according to similar properties and their weight

Metals

Metals lose electrons to gain an empty outer shell. They because positively charged.

Transition metals

They form positive ions when they react

Non metals

Non metals gain electrons to form a full outer shell. They become negatively charged

Group 1 alkali metals

• react with water to produce an alkali

• They lose an electron and become positively chaotic

• Reactivity increases as you go down the group, the outer shell is further away from the nucleus so there is less force of attraction

Group 7 halogens

• React with metals and form a -q charge as they accept 1 electron

• Reactivity decreases as you go down the group

• Boiling points increase as you go down the group

Group 0 - noble gases

• They are very unreactive because they have a full outer shell

Transition metals

• Gives a different number of electrons lost when it forms ions

• Harder and less reactive

• They form coloured compounds