Those materials which possess the characteristic of being hard, shiny, malleable, fusible, ductile, etc. are termed as metal. Ex iron, gold, silver, aluminium, copper, etc.
Physical Properties of Metals:
(a) Malleability:
It is that property of metals which allows them to be beaten into the thin sheets.
Due to presence of this property, the form of iron nail and aluminium wire may be changed on beating. The silver foils used for decorating sweets and also the aluminum foil used for wrapping food are possible due to malleability property of metals.
(b) Conductivity:
It is that property of metals which allows them to conduct heat and electricity easily.
Example- Metals like iron rod, nail, copper wire, etc. are good conductors of electricity.
(c) Ductility:
It is that property of metals which allows them to be drawn into the wires.Example: Metals like aluminium and copper wires are employed in electric connection.
(d) Sonorous:
It is that property of metals which produces ringing sounds on hitting.
Ringing property of Metal
(e) Lustrous:
It is that property of metals which makes them shine and their structures are capable of reflecting incident light.
Lustrous Property of Metal
Notes: Metals like sodium and potassium are soft and might be cut with a knife. Mercury is that the only metal which is found in liquid state at temperature. These are exceptions
2. Non -Metals:
Those materials which don't possess the characteristics of metals are termed as non-metal. Materials like coal and sulphur are soft and dull in appearance. They break down into powdery mass on tapping with hammer. they're non-sonorous and are poor conductors of heat and electricity. Few samples of non metals are sulphur, carbon, oxygen etc.
Chemical Properties of Metals & Non-Metals:
1. Reaction with Oxygen
(a) For Metals:
Generally, when metals are reacted with oxygen they'll form metallic oxides. And these metallic oxides are basic in nature.
Example-1: Rusting of Iron. Following is that the reaction to precise it.
Iron (Fe) + Oxygen (O2) + Water (H2O) → Iron Oxide (Fe2O3)Example-2: If a copper vessel is left open in presence of the moist air, then, a dull green coating are going to be observed thereon. The green material could be a mixture of copper hydroxide (Cu(OH)2) and copper carbonate (CuCO3). Following is that the reaction to precise it:
2Cu + H2O + CO2 + O2→Cu (OH)2 + CuCO3
Testing of nature of Rusting:
(i) Collect a spoonful of rust and dissolve it during a little amount of water.
(ii) The rust remains suspended in water. Shake the suspension well.
(iii) Test the solution with red and blue litmus papers. The red litmus turns blue.
So, generally metallic oxides are basic in nature.
Testing Nature of Rust
(b) For Non-metals:
Generally, non-metals also produce oxides when reacted with oxygen. But, in contrast to metals, these oxides are acidic in nature.
Testing the character of non metal:
(i) Take alittle amount of powdered sulphur during a deflagrating spoon then heat it.
(ii) As soon as sulphur starts burning, introduce the spoon into a gas jar/ glass tumbler.
(iii) Cover the tumbler with a lid to make sure that the gas produced doesn't escape.
Burning of Sulphur Powder
(iv) After it slow remove the spoon. Add alittle quantity of water into the tumbler and quickly replace the lid. Shake the tumbler well. Check the answer with red and blue litmus papers.
Testing of Solution with paper
(v) The name of the merchandise formed within the reaction of sulphur and oxygen is dioxide gas. When dioxide is dissolved in water sulphurous acid is made. Following is that the reaction to precise it:
Sulphur dioxide (SO2) + Water (H2O) → Sulphurous acid (H2SO3)
(vi) The sulphurous acid turns blue paper red.
Generally, oxides of non-metals are acidic in nature.
2. Reaction with Water:
(a) For Metals:
Some metals react vigorously with water like just in case of sodium. it's stored in kerosene.. While, some metals reacts very slowly with water like just in case of iron.
Reaction of Sodium with Water
(b) For Non-metals:
Generally, most non-metals don't react with water but there are some non-metals which are quite reactive in air like phosphorous, which is incredibly reactive and is kept in water to stop explosion.
3. Reaction with Acids:
(a) For Metals:
Generally, a metal reacts with acids and releases hydrogen gas with a ‘pop’ sound.
The presence of hydrogen gas is confirmed by bringing a burning matchstick or candle near the gas. And when the burning matchstick or candle produces pop sound then it means hydrogen gas has evoloved.
It is found that, copper doesn't reacts with acid while it reacts with a vitriol.
(b) For Non-metals:
Generally, non-metals don't react with acids.
4. Reaction with Bases:
(a) For Metals:
Generally, reactions of metals with bases releases hydrogen gas, like just in case of the many metals they react with caustic soda to supply hydrogen gas.
(b) For Non-metals:
Generally, reactions of non-metals with bases are complex.
5. Displacement Reaction:
During reaction if a metal replaces another metal from its compound then such reactions are called displacement.
Metals can actually be arranged as per their reactivity order, thus, a more reactive metal will always displace a less reactive metal from its compound but a less reactive one cannot replace a more reactive metal.
Example : When zinc is reacted with sulphate solution, then copper are going to be displaced by zinc as zinc is more reactive than copper. The blue colour of sulphate disappears and a powdery red mass of copper is deposited at the underside of the beaker. The reaction-
Copper Sulphate (CuSO4) + Zinc (Zn) → zinc sulfate (ZnSO4) + Copper (Cu)
Applications of Metals:
(i) Metals are generally employed in making of machines, automobiles, airplanes, cars, satellites, etc.
(ii) Some metals are employed in making wires like copper, etc.
(iii) Some metals are used for creating ornaments like gold, silver, etc.
Applications of Non - Metals:
(i) The oxygen necessary for all living beings to survive could be a non-metal.
(ii) Some non-metals are used as fertilizers to reinforce the expansion of plants.
(iii) Some non-metals are used for water-purification.
(iv) Some non-metals are used as antiseptic.
(v) Non-metals employed in crackers
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