Materials: Metals and Non Metals
MATERIALS : METALS
AND
NON-METALS
Y
Iron Coal
ou are familiar with a number of materials like iron, aluminium, copper, etc. Some materials have been given in Table 4.1.
Table 4.1 : Appearance and Hardness of materials Object /Material Appearance Hardness (Shiny/Dull) (Very hard/ Not very hard)
similar change if we try to beat a wood log ? Let us find out.
Activity 4.1
Take a small iron nail, a coal piece, a piece of thick aluminium wire and a pencil lead. Beat the iron nail with a hammer (Fig. 4.1). (But take care that you don’t hurt yourself in the process). Try to hit hard. Hit hard
Sulphur Aluminium Copper ----Fig. 4.1 : Beating an iron nail with hammer
Can you name the materials which are metals? The rest of the materials in Table 4.1 are non-metals. Metals can be distinguished from non-metals on the basis of their physical and chemical properties. Recall that lustre and hardness are physical properties.
also the aluminium wire. Then repeat the same kind of treatment on the coal piece and pencil lead. Record your observations in Table 4.2.
Table 4.2 Malleability of Materials Object/ Material Iron nail Coal piece Aluminium wire Pencil lead Change in Shape (Flattens/Breaks into pieces)
4.1 Physical Properties of Metals and Non-metals
Have you ever seen a blacksmith beating an iron piece or an article made up of iron, like a spade, a shovel, an axe? Do you find a change in the shape of these articles on beating? Would you expect a
You saw that the shape of the iron nail and the aluminium wire changed on beating. If they were beaten harder these could be changed into sheets. You might be familiar with silver foil used for decorating sweets. You must also be familiar with the aluminium foil used for wrapping food. The property of metals by which they can be beaten into thin sheets is called malleability. This is a characteristic property of metals. As you must have noticed, materials like coal and pencil lead do not show this
AND
NON-METALS
Y
Iron Coal
ou are familiar with a number of materials like iron, aluminium, copper, etc. Some materials have been given in Table 4.1.
Table 4.1 : Appearance and Hardness of materials Object /Material Appearance Hardness (Shiny/Dull) (Very hard/ Not very hard)
similar change if we try to beat a wood log ? Let us find out.
Activity 4.1
Take a small iron nail, a coal piece, a piece of thick aluminium wire and a pencil lead. Beat the iron nail with a hammer (Fig. 4.1). (But take care that you don’t hurt yourself in the process). Try to hit hard. Hit hard
Sulphur Aluminium Copper ----Fig. 4.1 : Beating an iron nail with hammer
Can you name the materials which are metals? The rest of the materials in Table 4.1 are non-metals. Metals can be distinguished from non-metals on the basis of their physical and chemical properties. Recall that lustre and hardness are physical properties.
also the aluminium wire. Then repeat the same kind of treatment on the coal piece and pencil lead. Record your observations in Table 4.2.
Table 4.2 Malleability of Materials Object/ Material Iron nail Coal piece Aluminium wire Pencil lead Change in Shape (Flattens/Breaks into pieces)
4.1 Physical Properties of Metals and Non-metals
Have you ever seen a blacksmith beating an iron piece or an article made up of iron, like a spade, a shovel, an axe? Do you find a change in the shape of these articles on beating? Would you expect a
You saw that the shape of the iron nail and the aluminium wire changed on beating. If they were beaten harder these could be changed into sheets. You might be familiar with silver foil used for decorating sweets. You must also be familiar with the aluminium foil used for wrapping food. The property of metals by which they can be beaten into thin sheets is called malleability. This is a characteristic property of metals. As you must have noticed, materials like coal and pencil lead do not show this