Elements - Metals and Non-metals

Elements are classified in different groups based on their properties.

Metals

Some common metals around us such as iron, copper, gold, silver sodium. calcium, magnesium, lead etc. are metals.

Metals are shiny in appearance and can reflect light. This property of metals is known as lustre. The lustre of metals makes them the material of choice for making jewellery, ornaments and statues. Metals can appear rusty or tarnished when they are exposed to air and moisture, but when polished, they again appear shiny.

Most metals are grey or silver in colour. Gold has a peculiar yellow colour, while copper is reddish.

Metals are usually hard and have more strength than non-metals. Metals such as iron, nickel, cobalt, copper, aluminium and lead are very strong, although some metals such as lithium, sodium and potassium are soft enough to be cut hot by a knife.

Most metals are in solid state, an exception is mercury which is in a liquid state. They usually have a high melting and boiling point.

Most metals possess the ability to be drawn into long and thin wires. This property is known as ductility.

Metals possess a property known as malleability which a the ability to be beaten into sheets. Most metals are malleable.

E.g. Aluminium foil

Bells are usually made up of metals or metal alloys. This is because metals produce a ringing sound when struck. This property is known as sonority and hence metals are said to be sonorous

Metals have the property of conducting heat. Hence, we use metal utensils to cook food and boil water This property of metals is known as thermal conductivity.

Metals are also used in electrical wiring, this is because they conduct electricity very easily.

This property of metals in known as conductivity.

Metals are good conductors of electricity.

Non-metals

Non-metals are all around us, the most important element for us, oxygen, is a non-metal.

Most non-metals possess properties opposite to that of metals. They are non-sonorus, bad conductors of heat and electricity, not ductile or malleable. They're usually brittle.

Most non-metals are gases. Sulphur, phosphorus and carbon are solids and bromine is a liquid at room temperature.

Most non-metals are gases. Sulphur, phosphorus and carbon are solids and bromine is a liquid at room temperature.

A few non-metals like diamond, graphite, and iodine have lustre.

The elements which show such properties are called inert gases or noble gases.

E.g. Helium, Argon, Krypton, Xenon and Radon.