5.
E Short answer type questions:
1. What are the properties of metals?
3 What is the essential condition for corrosion?
3 Why are electrical wires made up of copper?
4. How can you say non-metals are negatively charged ions?
5. What is displacement reaction?
F. Long answer type questions:
1. List the uses of metals.
2. What are the preventive measures to prevent corrosion?
3. Explain some chemical properties of non-metals.
Answers
Answer:
3. cause copper is a good conductor of electricity.
5. displacement reaction: when an element displaces another element from its compound this is displacement reaction.
LONG ANSWER
1. shiny metals like copper , silver and gold are used for decoration.like arts, jewellery and coins.
strong metals like iron is used for building structures such as train buses(all vehicles).
2. protective coating,alloyed steel (stainless), cathodic protection
Explanation:
1) lustre, malleability, ductility.
2)it should not have already an oxide layer like aluminium and it should be well exposed to air and moisture.
3)copper have high conducting capacity and heat loss is minimum and withstands high temperature.
4)for example if you take a reaction say Na+cl->Nacl here sodium gets positive charge as it is more electropositive metal,on the other side chlorine is electronegative and it is ready to accept electron to complete its octate so it gains negative charge if it has excess electons.we can explain the charge gaines by an atom on the basis of electropostivity and electronegativity.
5)it is a reaction in which an atom is displaced or exchanged by another atom in a molecule.
long type answers:
1)metals are used as conductors
2) they are used as ornaments
3) they are used in many industries for manufacturing vehicles
4)metals along with other combination of non metal or metal are used to make alloys
5)metals like aluminium are used to manufacture aircrafts.
2) there are many methods to prevent corrosion by just not letting it expose to air
1) painting the metal surface(varnishing)
2) lubricating the metal surface
3) 1.non metals are bad conductors of heat and electricity
2.non metals are electronegative in nature
3.non metals like carbon are of great use as they are used in manufacturing lighter objects and all organic substances are made up of carbon.