IMPORTANT TERMS

Malleability                   The property due to which metals can be beaten into thin sheets. 

Sonority                       Ability to produce a ringing sound when struck.

Ductility                        Physical ability of a metal to be easily drawn into thin wires.

Lustrous                      Materials having shiny appearance. E.g. Gold, silver

Corrosion                     Process of deterioration of metals due to atmospheric gases and moisture on its surface.

Salts                                          Compounds formed when a metal replaces hydrogen in an acid.

 

PHYSICAL PROPERTIES OF METALS AND NON-METALS

Physical Properties	Metals	Non-metals
Physical State	SoIid at room temperature. Mercury (liquid) is an exception.	Solids or gases at room temperature; Bromine is the only non-metal that exists as a liquid.
Hardness	Most metals are hard and strong.	Non-metals are generally soft and brittle. However, diamond is an exception.
Lustre	All metals are lustrous, i.e., they have a shiny surface.	Non-metals are not lustrous except graphite and iodine.
Ductility	Most metals are ductile, i.e., they can be drawn into wires.	Non-metals are not ductile.
Sonority	Metals are sonorous, i.e., they produce  a ringing sound when struck with a  hard object.	Non-metals are not sonorous. Produce a dull sound.
Malleability	Most metals are malleable. i.e., they can be drawn into thin sheets.	Non-metals are not malleable.
Tensile strength	Most metals have high tensile strength.	Non-metals have low tensile strength.
Electrical Conductivity	Good conductors of electricity	Poor conductors of electricity except Graphite
Thermal Conductivity	Good conductors of heat	Poor conductors of heat

 

 

CHEMICAL PROPERTIES OF METALS AND NON-METALS

Chemical Properties	Metals	Non-metals
Reaction with Oxygen	Metals react with oxygen to form metal oxides that are basic in nature.	Non-metals react with oxygen to form acidic oxides, which dissolve in water to form acids.
Reaction with Water	Most metals react with water produce a metal hydroxide or metal oxide and hydrogen gas.	Non-metals do not react with water.
Reaction with Acids	Metals react with acids and produce salts and hydrogen gas.	Non-metals do not react with acids.
Reaction with Bases	Most metals do not react with bases. Only a few, such as aluminium, lead, zinc react with strong bases.	The reactions of non-metals with bases are complex.

 

 

 

 

 

 

 

 

 

 

 

 

 

DISPLACEMENT REACTIONS

In a displacement reaction, a metal reacts with a salt solution and replaces the less active metal present in it. E.g. Iron is more reactive than copper so it reacts with the copper sulphate solution. Copper does not react with iron sulphate as it is less reactive than iron.

USE OF LITMUS PAPER

Litmus paper is used to test whether the given solution is acidic or basic in nature.

Red litmus paper when dipped in an acidic solution will remain red. It will turn blue when it is dipped in a basic solution. Metals combine with oxygen to form metal oxides, which are basic in nature. Metals - Basic - Blue (MBB).                   

Blue litmus paper is used to test whether a solution is acidic or not. If a blue litmus paper dipped in a solution remains blue, it indicates that the solution is either basic or neutral. Blue litmus paper when dipped in an acidic solution turns red. Non-metals react with oxygen to form acidic oxides. Non-Metals – Acidic – Red (NAR).

 

USES OF SOME COMMON METALS

Zinc is used to make galvanised iron pipes and sheets to protect them from corrosion.

Gold, silver and platinum are used for making jewellery. 

Iron is used for making automobiles, pipes, machinery, nails etc.

Aluminium is used for making cooking utensils and electrical cables.

 

USES OF SOME COMMON NON-METALS

Graphite is a non-metal, which is used as a dry lubricant in machine parts and to make the lead

of pencils.

 

Phosphorous is used to make safety matches and in the fireworks industry.

 

Sulphur is used in the manufacturing of compounds such as sulphuric acid and is also an important constituent of gunpowder.

 

Hydrogen is used for the synthesis of ammonia & methyl alcohol and in welding torches.

 

INTERESTING FACTS

• Bronze is a metal alloy made from copper and tin.
• The word metal comes from the Greek word 'Metallon', which means to mine or excavate.
• Platinum is the rarest and heaviest of all the precious metals.
• Iron is the most abundant metal in the universe.
• Tungsten has the highest melting point. It melts at 3400 degrees Celsius. It is used as a filament in some light bulbs.
• The human body consists of plenty of non-metals. Water is a compound of two non-metals: hydrogen and oxygen.
• Phosphorus, Carbon and nitrogen are amongst the non-metals that are present in the human body.
• Gold, silver and platinum are known as Noble metals because of their resistance to oxidation and corrosion.