Physical Properties of metals
Metals are widely used in our daily life. For example, you must have used vessels made of aluminum, copper, brass and stainless steel. Metals are used for the construction of bridges, automobiles, aero planes, ships, trains, etc. Some of the metals, like gold, silver, copper, lead, mercury, tin, etc., have been in use since ancient times. During the Bronze age, people produced copper by heating a rock containing copper with carbon. In fact, metals are very important for the national economy of any country. Some metals, such as titanium, chromium, manganese, zirconium, etc., are classified as strategic metals. That is, they are essential for the country’s economy or its defence. These metals and their alloys are used in atomic energy, space science projects, jet engines, highgrade steels, etc.
A metal is an element which can form positive ions by the loss of electrons. The number of electrons lost by an atom is known as the valency of the metal.
Thus, sodium, magnesium, copper and aluminium are metals. They are metals because they can form positive ions by the loss of electrons. Let us now study some of the characteristic properties of metals.