Physical Properties of Metals are
Malleability
It means that metal can be beaten into thin sheets
Ductility
It means that metal can be stretched to form thin wires
Good conductors of Electricity
It means that electricity can pass through the metal
Good conductor of Heat
It means that heat can pass through the metal
Sonorousness
Metals produce ringing sound when hit hard, it means they are sonorous
Lustrous
Metals are shiny in nature, this means they are lustrous
What are Malleable and Non Malleable Items
Malleable Items
Those items which can be beaten into thin sheets is called Malleable item
Example
Metals like Iron, Steel, Zinc, Aluminium,Copper,Gold,Silver
Exception
Metals like Sodium and Potassium are soft and can be cut with a knife
Non Malleable Items
Those items which cannot be beaten into thin sheets are called Non Malleable item
The property of non metals that they break on beating is known as Brittleness
Example
Non Metals like Coal, Diamond,Lead,Sulphur,Phosphorus
Note- Diamond is the hardest non metal
What are Ductile and Non Ductile Items
Ductile Items
Those items which can be formed into thin wires are ductile items
Example
Metals like Iron,Gold,Silver,,Zinc and Copper are ductile,except mercury which is in liquid form
Non Ductile Items
Items which cannot be formed into thin wires are known as Non Ductile items
Example
Non Metals like Hydrogen and Oxygen
What are Good and Bad conductors of electricity
Good Conductors
Those item which easily allow electricity to pass through them
Example
Metals like Copper are used to make wires
Bad Conductors
Those item which do not allow the electricity to pass through them
Example
Non Metals like Wood and Plastic are used to make handles of utensils because
They are bad conductors of heat and do not allow heat to pass through them
So,they are used to make handles of screw drivers
Exception
Non Metals are normally bad conductor of electricity
However
Graphite is a non-metal but it is a good conductor of electricity.
What are Good and Bad conductors of Heat
Good conductors of heat
Those item which allow heat to pass through them
Example
Metals like Gold and Silver
Bad conductors of heat
Those item which do not allow heat to pass through them
Example
Non Metals like Wood and Plastic are used to make handles of utensils because they are bad conductors of electricity and do not allow heat to pass through them
What are Sonorous and Non Sonorous Items
Sonorous Items
Items which produce a ringing sound when hit with a hard object
Example
We use Iron bells in bicycles because Iron is Sonorous
Non Sonorous Items
Items which do not produce a ringing sound when hit with a hard object
Example
Non metals like Iodine and Carbon do not produce a ringing sound
How to find whether a particular object is a metal or non metal
We can find whether a particular object is metal or a non metal by striking it with a hammer
If it is a metal it will produce a ringing sound
If it is a non metal,it will not produce a ringing sound.
What are Lustrous and Non Lustrous Items
Lustrous Items
Items which are shiny are lustrous objects
Example
Metals like Gold and Silver
Non Lustrous Items
Items which are not shiny are non lustrous objects
Example:- Non Metals like Sulphur and Phosphorous
Examples of Metals And Non-Metals in Solid, Liquid and Gaseous form:-
Metals
Solid : Aluminium, Iron.
Liquid: Mercury, Zinc
Gas: There is no metal which exists in gaseous form.
Non- Metals
Solid: Sulphur and iodine.
Liquid: Bromine, Phosphorus.
Gas: Oxygen, Helium.
Questions
NCERT Question 1 - Which of the following can be beaten into thin sheets?
(a) Zinc
(b) Phosphorus
(c) Sulphur
(d) Oxygen
NCERT Question 2 - Which of the following statements is correct?
(a) All metals are ductile.
(b) All non-metals are ductile.
(c) Generally, metals are ductile.
(d) Some non-metals are ductile.
NCERT Question 3 (b) - Fill in the blanks :
Metals are…………….. conductors of heat and………………….. .
NCERT Question 4 (d) - Mark ‘T’ if the statement is true and ‘F’ if it is false.
Coal can be drawn into wires.
NCERT Question 5 - Some properties are listed in the following Table. Distinguish between metals and nonmetals on the basis of these properties.
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Properties |
Metals |
Non-metals |
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1. Appearance |
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2. Hardness |
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3. Malleability |
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4. Ductility |
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5. Heat Conduction |
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6. Conduction of Electricity |
NCERT Question 6 - Give reasons for the following :
(a) Aluminium foils are used to wrap food items.
(b) Immersion rods for heating liquids are made up of metallic substances.
NCERT Question 8 - In the following Table some substances are given in Column I. In Column II some uses are given. Match the items in column I with
those in Column II
