Uses of common metals. The importance of metals. Which metals are used most. Quantities of some common metals used. How to choose a metal. Common physical properties. 1.Metals conduct electricity. 2.Metals conduct heat. 4.Metals are malleable.
Quantities of some common metals used
1.Metals conduct electricity
2.Metals conduct heat.
4.Metals are malleable.
3.Metals are shiny (though a few metals turn dull after exposure to air)
5Metals are ductile.
Differences in physical Properties
1. Hardness and strength
3. Melting point
Two important factors are
The abundance of the metal in the earth.
The cost of extraction.
good electrical conductor ,ductile.resistant to corrosion,not too expensive
Aluminum.Cheaper,much lighter (therefore pylons can be made more
Cheaply to support the lighter weight).It is also a good electrical conductor
And resistant to corrosion
Too soft,not very ductile,reacts with air and water
To provide more strength to the cable.
The figure shows overhead
Why are the handlebars not solid chromium?
The handlebars of a bicycle are made of iron covered with a thin layer of chromium(Cr)
(a) Some advantages of making a car from gold and not iron
Shiny,attractive, malleable, resistant to corrosion
(b) Some disadvantages.
(2)The table below gives the relative properties and prices of four metals
Decide which of the four metals,A to D,you would choose to make the following,
objects.Give reasons for your choice.
B-light,corrosion resistant,not too expensive
B-ductile,light,good electrical conductor,corrosion resistant,not too expensive
(b) Electrical wires
A-cheap,fair corrosion resistant (can be painted)
(c) A bridge
(d) A window frame
D-malleable,fair corrosion resistant,not too expensive
THANK YOU of four metals