Metals are typically hard, shiny materials that conduct heat and electricity well. They exist as solids at room temperature, except for a few like mercury. Metals reflect light well due to their loosely bound outer electrons. Other key properties include malleability, ductility, conductivity, density, and high melting and boiling points. Metals conduct electricity and heat well because their molecular bonding allows free electrons to move freely within their structure when a current is applied.

1. Metals
Kalika Presents to you

2. What is aMetal?
• A metal is a material that is typically
hard, opaque, shiny, and has good
electrical and thermal conductivity.

4. Propertiesof Metals
• Physical state: Most of metals exists
as solids at room temperature except
mercury, gallium & cesium.
• Luster: Metals have the quality of
reflecting light from its surface and can
be polished e.g., gold, silver and
copper.

5. Why Metals Shine?
• Metallic solids and liquids share the
outer electrons freely. When light
shines on a lustrous metal, the loosely
bound electrons reflect incoming light,
giving the metal a shiny appearance.

6. Propertiesof Metals
• Malleability: Metals have the ability to
withstand hammering and can be made
into thin sheets known as foils.
• Ductility: Metals can be drawn into wires.
• Hardness: All metals are hard except
sodium and potassium, which are soft and
can be cut with a knife.

7. Propertiesof Metals
• Conductivity: Metals are good
conductors. Silver and copper are the
two best conductors of heat and
electricity. Lead is the poorest
conductor of heat.

8. The switch
is off

9. The switch is
now on

10. Whyare Metals GoodConductors?
• Metals are such good conductors of
heat and electricity all because the way
they are molecularly bonded.
• They contain free electrons(delocalized)
in their valence shell, these free
electrons move within structure of
metal when an electric current is
applied.

11. Propertiesof Metals
• Density: Metals have high density and are
very heavy. Iridium and osmium have the
highest densities where as lithium has the
lowest density.
• Melting and Boiling point: Metals have
high melting and boiling point. Tungsten
has the highest melting point where as
silver has low boiling point. Sodium and
potassium have low melting points.

12. Propertiesof Metals
• Sonority- Metal are sonorous, meaning
that metals have a unique ringing
sound if you strike them with
something hard.
• Tensile Strength- The ability of metal
to withstand a stretching force.