Metallic bonding

Where are metalloids located and what general properties do they have

They are located between metals and non metals

Metalloids have some properties of metals and other properties of non metals

What do metal structures have

In metals the electrons in the outer shell are delocalised

Describe the structure and features of lithium metal

Lithium atoms have 3 protons in the nucleus and total of 3 electrons - 1 electron on its outer shell - in metals the electrons in the outer shell are delocalised

Bc the lithium atom have donged their outer electron its now described as a 1+ cation

The negative delocalised electrons are strongly attracted to the +ve cations by electrostatic forces of attraction

Where does the electrostatic force of attraction in metal come from

The negative delocalised electrons which are strongly attracted to the +ve cations (by electrostatic forces of attraction

Note

The overall structure of the metal is known as a giant metallic lattice

What are the features of a giant metallic lattice

1- the cations are fixed in place and cannot move

2- the delocalised electrons are free to move

3-metals are good conductors of electricity when they are both solids and liquids

4- most metals have relatively high melting and boiling points

5- metals do not dissolve

Why are metals good conductors of electricity when they are both solids and liquids

Voltage across the metal- the delocalised electrons are attracted towards the positive pole and move towards it- in this case the delocalised electrons are acting as mobile charge carriers enabling metals to conduct electricity

Why do most metals have relatively high melting and boiling points

Because of the strength of the metallic bond - the delocalised electrons have a strong electrostatic attraction to the cations - it takes a lot of energy to overcome this attraction. Therefore metals generally have high melting and boiling points

Why don’t metals dissolve

Because when we add a metal to water, in many cases the metal simply reacts with the water rather than dissolving

Why does the beryllium atom(2 e- outer shell) have a higher melting and boiling point than lithium(1 e- outer shell)?

Beryllium has 2 outer electrons which are delocalised- therefore the strength of the metallic bond (electrostatic forces of attraction) is greater than in lithium- so beryllium has a higher melting and boiling point