METALS AND NONMETALS

Question 1

Physical properties of metals

Answer 1

1. Metals are lustrous i.e. they have a shiny coating on their surface
   2.Metals are generally hard and are solid at room temperature
   3.Metals are malleable(Tendency to be beaten into sheets )
   The most malleable elements are gold and silver
   4.Metals are ductile(Can be stretched into thin wire easily)
   The most ductile element is gold ,1 g of gold can be drawn into a wire of about 1 km
   5.Metals are good conductors of heat and electricity .Most of the cooking vessels are made up of aluminum and copper.
   6.Metals are sonorous (Produce ringing sound on being beaten)

Question 2

Physical properties of non metals:

Answer 2

1.They are non lustrous
2.Not malleable
3.Not ductile
4.Not sonorous
5.Poor conductors of heat and electricity
6.Are generally found in solid and gaseous state

Question 3

EXCEPTIONS

Answer 3

1.All metals except mercury exist as solids at room temperature. Mercury is liquid at room temperature
2.Bromine is the only non metal which is liquid at room temperature
3.Metals have high melting points but gallium and cesium
have very low melting points. These two metals will melt if you keep them on your palm.
4.Iodine is a non-metal but it is lustrous.
5.Carbon is a non-metal that can exist in different forms. each form is called an allotrope. Diamond, an allotrope of carbon, is the hardest natural substance known and has a very high melting and boiling point. Graphite, another allotrope of carbon, is a conductor of electricity.
6.Alkali metals (lithium, sodium, potassium) are so soft that they can be cut with a knife. They have low densities and low melting points.
7.Mercury is a poor conductor of heat
8.Lead is a poor conductor of electricity

Question 4

Reaction of metal with air