Metals & Non-metals - Class 10th Science
Classification
Substances can be classified into two categories i.e. between metals and non-metals on the basis of some of their properties.
Metals:
There are many substances that are known as metals because of some of their unique properties, such as iron, copper, gold, silver, sodium, aluminium, etc.
Physical properties of Metals:
Metallic Lusture:
Metals have shining surfaces. This property of metals is called metallic luster. Because of this property (metallic luster) gold, silver, platinum, etc. are used to make jewelry.
Hardness:
Metals are generally hard. But hardness varies from metal to metal. But, sodium is an exception which is very soft. Sodium metal can be cut using a knife.
Because of its hardness iron metal is used in making garter of bridges, rail lines, rail compartments, car bodies, etc.
Malleability:
Metals are malleable. Metals can be beaten into thin sheets. This character of metals is called malleability. Because of this character, iron metal is used to make thin sheets that are used in making car body, containers, etc.
Gold and silver are most malleable metals that’s why these metals are used in making jewelries.
Ductility:
Metals are ductile. Metals can be drawn into thin wires. This character of metals is called ductility. Because of this character of ductility, iron is used in making wires which are tied up to make strong ropes. Ropes made of iron are used in cranes, bridges, etc.
Gold is the most ductile metal. Gold is such ductile that about 2km of wire can be drawn from one gram of gold.
Good conductor of Heat:
Metals are good conductors of heat. Because of this property cooking utensils are made of metals, such as aluminium, copper, iron, etc.
Good conductor of electricity:
Metals are good conductors of electricity. Because of this property copper and aluminium metals are used to make electric wires.
Sonorous:
Metals produce ringing sounds when beaten. Because of this property metals are used to make bells in schools, temples, and churches. This property of metals to produce ringing sound is called sonorous.
Physical state:
Metals are solid at room temperature except for mercury which is liquid at room temperature.
Melting and boiling points:
Metals have high melting and boiling points. But Gallium and Cesium have very low melting points. They have such low melting points that they melt even by keeping on palm.
Non-metal:
There are many elements that are called non-metals because they have some unique properties. For example, carbon, sulfur, iodine, oxygen, etc. These properties are generally opposite to metals.
Physical properties of Non-Metals:
Lusture:
Non-Metals do not have shining surfaces like metals except diamond and iodine.
Hardness:
Non-metals are soft. But, diamond which is an allotrope of carbon is the hardest natural substance so far known.
Malleability:
Non-Metals are not malleable. Non-Metals cannot be beaten into thin sheets. When a non-metal is beaten it is broken into pieces. Thus, non-metals are brittle.
Ductility:
Non-Metals are not ductile, i.e. non-metals are brittle. Non-Metals can not be drawn into thin wires.
Bad conductor of Heat:
Metals are bad conductors of heat.
Bad conductor of electricity:
Non-Metals are bad conductors of electricity except graphite which is an allotrope of carbon.
Non-Sonorous:
Non-Metals do not produce ringing sounds when beaten, thus non-metals are non-sonorous.
Physical state:
Some non-metals are solid, some are liquid and some are gas at room temperature.
Melting and boiling points:
Non-metals have low melting and boiling points. But, diamond, an allotrope of carbon has very high melting and boiling points.