Metals

• In metals the atoms are very closely packed together and have special type of bonds known as metallic bonds. Because of close packing of atoms metals are quite hard.

Properties of Metals:

1. Metals are solids at room temperature.

Exception: mercury is liquid at room temperature. Gallium and Cesium become liquid at a temperature slightly above room temperature (303 K)

2. Metals are hard.

Exception: Sodium and potassium are soft metals.

3. In a metal constituents or atoms are very closely packed in space. The close packed arrangement is known as crystal lattice.
4. Metals have high tensile strength.
5. Metals are sonorous which means when they are bent or hit, they produce a tinkling sound.
6. Metals generally have high melting and boiling points.
7. Metals have shining surface. This property is known as luster. Like - Silver-grey or golden-yellow surfaces.

8. Metals are malleable i.e. they can be beaten to form very fine thin sheets.

For example:

• Gold and silver metals are some of the best malleable metals.
• Aluminium foils are used for packing food items like biscuits, chocolates.
• Copper metal is also highly malleable. So, copper sheets are used to make utensils and other containers.

9. Metals are ductile i.e. they can be drawn (or stretched) into thin wires.

Copper and aluminium metals are also very ductile and can be drawn into thin wires which are used electrical wiring.

10. Metals are good conductors of heat and electricity.

Cooking utensils and water boilers, etc., are usually made of copper or aluminium because they are very good conductors of heat.

The electric wires are made of copper and aluminium metals because they are very good conductors of electricity.