chemistry 2 lesson 2.4 giant metallic structures aqa additional science
TRANSCRIPT
Aims
Class work Bonds in Metals
LO’s• Why do metals have their properties?
Write it down!! Page 46© C Meyer
All• Know how metal atoms are put
together• Know the properties of metalsMost• Explain why metals have their
propertiesSome• Explain how metals conduct
electricity
Aims
m1
Metal Structure• Take ping pong ball rafts • Place a set as the first layer• Sit a second layer on the first• Sit a third layer either
• Over the first• Or
• With their centres not in line with the first layer
10 mins
Why do metals have their properties?Understanding their structure should help explain their properties
Gold/copper
Zinc/nickel
Why do metals have their properties?
• Metal atoms form a giant lattice similar to ionic compounds.
• Metals are not brittle.
• The metal atoms are the same and exist in simple structures.
• If something hits the substance, it simply moves to the next layer along. Again, like layers of paper. This is why they are ductile.
Blow
Bonding and physical properties
Copy diagram and note why metals are ductile m3
• Take a petri dish• Add some soap solution• Use a pipette to blow small bubbles and fill
the petri dish• What do the atoms do?• What happens if you GENTLY squeeze the
walls of the petri dish• What happens if you put a big bubble in
the rows?
Why do metals have their properties?
10 mins
Lets make a different atom model to see how the atoms move as the metal is deformed
How do metals bond?
m2
Why do metals conduct?
•Outer electrons arefree to move all
overthe lattice in a
“sea of electrons” (delocalised).
Delocalised electronswill move to conductelectricity (and heatrapidly)
Complete the Table and fill in the blank columns.
YesYesLowNoE
Small or giant?
Yes
No
No
Yes
Conduct when
molten
NoHighNoD
NoHighNoC
NoLowYesB
YesHighNoA
Metal
Ionic
Small Mol
Giant Mol
Conduct as solid
Melting Point
Soluble in petrol
Giant Metal
Small Small Mol
Giant Giant Mol
Giant Ionic
Substance E is peculiar:
Can you suggest an actual substance that E could be?
Can you explain the low melting point?
MetalGiant
Activity
Substance
Which of these will conduct as both solid and liquid?
A. metal
B. ionic
C. small molecules
D. giant molecules
What have I learnt?
Which of these will conduct when liquid but not when solid?
A. small molecules
B. giant molecules
C. metal
D. ionic
What have I learnt?
Which of these will not conduct at all and is hard to melt?
A. small molecules
B. giant molecules
C. metal
D. ionic
What have I learnt?
Which of these will conduct as both solid and liquid?
A. metal
B. ionic
C. small molecules
D. giant molecules
What have I learnt?
Which of these will conduct when liquid but not when solid?
A. small molecules
B. giant molecules
C. metal
D. ionic
What have I learnt?
Which of these will dissolve in solvents like petrol?
A. small molecules
B. giant molecules
C. metal
D. ionic
What have I learnt?
Which of these will not conduct at all and is hard to melt?
A. small molecules
B. giant molecules
C. metal
D. ionic
What have I learnt?