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• Metal: Metals are the elements which shows properties like luster, hardness, malleability, ductility, etc.
• Non Metals: Non Metals are the elements which do not show properties like metals.
• Properties of Metals and Non-Metals / Difference between Metals and Non-Metals:

Property	Metals	Non Metals
Lustre	Yes	No
Hardness	Yes	No ( are generally soft)
Malleability (Can be beaten into sheets)	Are malleable	No malleability
Ductility (Can be drawn into wires)	Are ductile.	No ductility
Heat Conduction	Good conductor of heat	Bad conductors of heat
Electrical Conduction	Good conductors of electricity	Bad conductors of electricity (used as an insulator)
Sonority (Produces sound)	Are sonorous	No sonority

• Varying behaviour of metals and non-metals / Exceptions in metals and non-metals.
• Metals:
1. Among metals, Mercury is only liquid metal.
2. Metals have high melting point, Gallium and Caesium are metals with low melting point.
3. Metals are hard,but Lithium, Sodium, Potassium are soft.
• Non-Metals:
1. Iodine is only non-metal which posses lustre.
2. Carbon in non-metals show different forms like graphite, diamond, etc (property of allotropy)
• Chemical properties of Metals:
• Burning of metal in air:  Metal + Oxygen ⟶ Metal Oxide

• Anodising: [Refer video to understand in detail] Aluminium when exposed to air forms thin oxide layer which prevents further corrosion. Thin layer of oxide is made thicker with help of anodising. In this process, aluminium article is anode and electrolytic solution used is sulphuric acid. When current is passed hydrogen gas is evolved at cathode and oxygen at anode. Oxygen gas reacts with  aluminium article and makes a thick oxide layer. This process is called anodising:
• Amphoteric nature of metal oxide:  Metal Oxide acts as  base with acid;  and act as acid with a base.

• Dissolution of metal oxide in water: Form alkalis in water.

• Reaction of metals with water:  

Metal + Water → Metal oxide  + Hydrogen

Metal oxide + Water → Metal hydroxide

• Reaction of highly reactive metal with water: Forms metal hydroxide and hydrogen gas and heat is released.

• Reaction of comparatively less reactive metal with water: Forms metal hydroxide and released hydrogen gas stick to metal, hence, metal floats on water.

• Reaction with moderately reactive metals with water: Reacts with steam to form metal oxide  and hydrogen gas is released.

• Reaction with least reactive metal with water: Metal like lead, copper, silver and gold do not react with water.
• Reaction of metal with acids:
1. Most of metals forms salt and releases hydrogen gas.

 

1. Some metals reacts with dil. Nitric Acid (HNO3) and produces salt , nitrogen  oxides(N2O, NO, NO2) and water.

• Reaction of metals with solution of other metal salts:  Reactive metals displaces less reactive metals from their salt solution

Reactive Metal A+ Salt solution of less reactive Metal B →Salt solution of  Reactive

          Metal A + Less reactive Metal B

• If less reactive metal is reacted with salt solution of more reactive metal no reaction takes place.
• Reactivity series : List of metals in decreasing  order of reactivity.

• Reactions of metals and nonmetals : Metals reacts with nonmetals to form ionic bond.

• How is ionic bond formed?:
1. Metal donates electron to have completely filled outermost shell and gain stability. Hence, metal forms positive ion,

1. Nonmetal accepts electron to  complete outermost shell and gain stability. Hence, nonmetals form negative ion.

1. Positive and negative ion, together form ionic bond or electrovalent bond.

• Properties of ionic compounds:
• Ionic compounds are in solid state and burns with coloured flame.
• They are water soluble but insoluble in solvents like kerosene, petrol, etc.
• Have high melting point and boiling point.
• In aqueous solution, ionic compounds conducts electricity.
• Occurrence of metals: Metals from earth crust occurs in form of elements or compound called minerals. Least reactive metals occurs in free form (Gold, Silver). Middle reactive metals (Copper, Iron) occurs in form of sulphide, oxides and carbonate. The reactive metals occurs in combined form (Sodium occurs as Sodium Chloride).
• Extraction of metals:
• Ores: Mineral containing high percentage of metals.
• Gangue: Impurities (soil, sand,etc) present in ore.
• Concentration of ores: Process through which gangue is separated from ores with suitable technique based on physical and chemical properties. E.g. iron is easily separated from gangue, due to magnetic properties of iron.
• Extracting metals of low reactivity: Low reactivity metal can be obtained from their ores by heating in air called as roasting. Eg. Extraction of mercury from the ore cinnabar.

• Extracting metals of middle reactivity: Metals of middle reactivity occurs in sulphides or carbonate form, they are converted to oxides by roasting or calcination respectively. Metals are obtained from metal oxide by reduction or displacement reaction. [Refer the video to understand in detail]
1. Roasting:

1. Calcination:

1. Reduction: Zinc oxide reduced to zinc by removal of oxygen.

1. Displacement: Aluminium being more reactive displaces manganese less reactive metal forming aluminium oxide and manganese metal.

1. Thermite reaction: Liquid iron is formed by displacement reaction, this is used to fill cracks of railway track or machine part.

• Extracting metal with high reactivity: Highly reactive metals are in combined state, hence, they cannot be reduced using carbon, therefore, electrolytic reduction is carried out. E.g. sodium is extracted from sodium chloride using electrolytic reduction. [Refer the video to understand in detail]

Na⁺+ e⁻ → Na       [Sodium metal collected at cathode]

2Cl⁻ → Cl2  + 2e⁻   [Chlorine gas liberated at anode]

    

• Refining of metals: Extracted metals from extraction process contains impurities. These impurities can be removed by electrolytic refining. In electrolytic reduction, impure metal is made as anode and pure metal is made as cathode. Electrolytic solution is consist of molten salt solution. When current is passed anode dissolves in solution and same amount of metal is deposited at cathode, while impurities settles at anode known as anode mud. [Refer the video to understand in detail]
• At anode: Cu(s) → Cu²⁺(l) + 2e⁻
• At cathode: Cu²⁺(l)  + 2e⁻ → Cu(s)

• Corrosion: Damage to metals due to attack by substances like acid rains, moisture, etc. For example blackening of silver articles, rusting of iron, etc.
• Prevention of Corrosion:
• Basic method: Rusting can be prevented by painting, oiling and greasing iron material.
• Galvanising : [Refer the video to understand in detail]

• Iron or steel is coated with zinc. Coating prevents directing contact with air and water hence, prevents corrosion. Even if coating breaks zinc gets corroded, preventing the substance.
• Alloying: A process in which one substance is mixed with another, which can be metal or nonmetal. The new substance formed will be of desired properties. E.g. pure iron is soft, it is mixed with 0.05% of carbon to make it hard and strong. Alloy is obtained by melting primary metal and then adding appropriate amount of metal to it.
• Alloy has low electrical conductivity and low melting point than pure metal.
• Solder used in welding electrical wires is alloy of lead and tin, with low melting point than pure metal.
• Amalgam: Alloy made up of mercury.