Question

There are two boxes, one is made of metal and the other made of wood , which are similar in appearance. How will you find out which box is made of metal?

Answer 1

I will find it out by keeping it in direct sun for 4-5 hours...... where the metal will become hot and the wood box will remain the same as it is...... hope it helps...... plz mark as brainliest answer.....

Answer 2

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Metals and Non metals

home Material Metals and Non metals

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Table of Content                                             4.1 Physical Properties of Metals and Non-metals4.2 Chemical Properties of Metals and Non-metals4.3 Uses of Metals and Nonmetals  KEYWORDSExtended Learning — Activities and ProjectsWhat you have learntEXERCISE

TABLE OF CONTENT4.1 PHYSICAL PROPERTIES OF METALS AND NON-METALS4.2 CHEMICAL PROPERTIES OF METALS AND NON-METALS4.3 USES OF METALS AND NONMETALSKEYWORDSEXTENDED LEARNING — ACTIVITIES AND PROJECTSWHAT YOU HAVE LEARNTEXERCISE

You are familiar with a number of materials like iron, aluminium, copper, etc. Some materials have been given in Table 1.

Table 1 : Appearance and Hardness of materials

Object/MaterialAppearance(Shiny/Dull) Hardness(Very hard/Not very hard) Iron  Coal  Sulphur  Aluminium  Copper  -----    

Can you name the materials which are metals? The rest of the materials in Table 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.

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 similar change if we try to beat a wood log ?
Let us find out.

Activity 1Take 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. 1). (But take care that you don’t hurt yourself in the process). Try to hit hard. Hit hard



Fig. 1:Beating an iron nail with hammer

also the aluminium wire. Then repeat the same kind of treatment on the coal piece and pencil lead. Record your observations in Table 2.

Table 2 Malleability of Materials

Object/MaterialChange in Shape (Flattens/Breaks into pieces)Iron nailFlattens Breaks into pieceCoal pieceFlattens Breaks into pieceAluminium wireFlattens Breaks into piecePencil leadFlattens Breaks into piece

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 property. Can we call these as metals?

Can you hold a hot metallic pan which is without a plastic or a wooden handle and not get hurt? Perhaps not! Why? Try to list some other experiences in which a wooden or plastic handle protects you from being hurt while handling hot things. On the basis of these experiences what can you say about the conduction of heat by wood and plastic?