Metallic Bonds

Metallic Bonds

Dr Ahmed

Metallic Bonds

• Secure metallic bonding in diagrams

• Describe the metallic bond

• Explain how metal atoms form metallic bonds

Quick recap on bonding so far...

Multiple Choice

What is the charge on an oxygen ion?

• +2

• +1

• -2

• -1

Open Ended

How does an atom become an ion?

Open Ended

List some properties of ionic compounds

Multiple Choice

Why do small covalent molecules have low boiling and melting points?

• Covalent bonds are weak

• They have weak intermolecular bonds

• They are very small so have less bonds

• Ionic bonds are strong

Multiple Choice

HCl has what kind of bonding?

• Ionic

• Simple Covalent

• Metallic

• Giant covalent

Multiple Choice

NaCl has what kind of bonding?

• Ionic

• Simple Covalent

• Metallic

• Giant covalent

Multiple Choice

Fullerene has what kind of bonding?

• Ionic

• Simple Covalent

• Metallic

• Giant covalent

Definition

Metallic bonding is the strong attraction between closely packed positive metal ions and a 'sea' of delocalised electrons.

Properties of metallic bonds

• Once the metal atom loses electrons they move randomly

Properties of metallic bonds

• If you apply an electric current the electrons can carry the charge through the solid metal.

• Metallic bonds CAN conduct electricity

Properties of metallic bonds

• Atoms are arranged in a regular arrangement

• Once hit they can therefore move

• This is why metals are MALLEABLE

• Metals are also DUCTILE

Open Ended

Write a list completing each word to describe the properties of metals:

Metals are:

S_____

C_____ E______

H____ M_______ P________

M________

D________

So how do we strengthen metals??

Alloys

• An alloy is a mixture of a metal with another element

• This can be another metal or a non-metal (usually carbon)

• The disorderly arrangement makes the metal less malleable and much stronger.

Quick Task - Google some uses of alloys. In the Teams chat write down what the alloy is made of and what it is used for. You've got 5 mins

Multiple Choice

Metallic bonds are held together by...

• The attraction of positive and negative ions

• Sharing electrons

• The attraction of positive ions to a sea of delocalised electrons

• Tranfer of electrons

Open Ended

Describe why metals are malleable and ductile

Open Ended

Why are metals good conductors of heat and electricity?

Open Ended

Explain why Alloying a metal makes it stronger.