Metals
Physical Properties of Metals
Hardness
Most of the metals are hard, except alkali metals, such as sodium, potassium, lithium, etc. are very soft metals. These can be cut by using a knife.
Strength
Most of the metals are strong and have high tensile strength. Because of this, big structures are made using metals, such as copper (Cu) and iron (Fe). (Except Sodium (Na) and potassium (K) which are soft metals).
State
Metals are solid at room temperature except for mercury (Hg).
Sound
Metals produce ringing sound, so, metals are called Sonorous. Sound of metals is also known as Metallic sound. This is the cause that metal wires are used in making musical instruments.
Conduction
Metals are a good conductor of heat and electricity. This is the cause that electric wires are made of metals like copper and aluminium.
Malleability
Metals are malleable. This means metals can be beaten into a thin sheet. Because of this property, iron is used in making big ships.
Ductility
Metals are ductile. This means metals can be drawn into thin wire. Because of this property, a wire is made of metals.
Melting and Boiling Point
Metals have generally high melting and boiling points. (Except sodium and potassium metals which have low melting and boiling point.)
Density
Most of the metals have a high density.
Colour
Most of the metals are grey in colour. But gold and copper are exceptions.
Non-Metals
Physical properties of non-metals
Hardness
Non-metals are not hard rather they are generally soft. But the diamond is an exception; it is the hardest naturally occurring substance.
State
Non-metals may be solid, liquid or gas.
Lustre
Non-metals have a dull appearance. Diamond and iodine are exceptions.
Sonority
Non-metals are not sonorous, i.e., they do not produce a typical sound on being hit.
Conduction
Non-metals are a bad conductor of heat and electricity. Graphite which is allotrope of carbon is a good conductor of electricity and is an exception.
Malleability and ductility
Non-metals are brittle.
Melting and boiling point
Non-metals have generally low melting and boiling points.
Density
Most of the non-metals have low density.
Colour
Non-metals are in many colours.
The topics discussed in the chapter are as follows:
- Alloys
- Corrosion
- Prevention of Corrosion
- Chemical Properties
- Basic oxides of metals
- Amphoteric oxides of metals
- Reactivity Series
- Reaction of Metals with Water or Steam
- Reaction of Metals with Acid
- Reaction of Metals with Bases
- Extraction of Metals and Non-metals
- Roasting
- Calcination
- Enrichment of Ores