Quick Notes Of Metals and Non-metals 10th

Metals have a shiny surface. This property is called metallic luster.

Metals are generally hard.

Metals are malleable, which means they can be beaten into thin sheets. Gold and Silver are the most malleable metals.

Metals are ductile, which means they can be drawn into thin wires. Gold is the most ductile metal. A wire of 2KM length can be drawn from 1gm of gold.

Metals are malleable and ductile due to which they can be given different shapes.

Metals are good conductors of heat and have high melting points. Silver and Copper are the best conductors of heat. Lead and Mercury are comparatively poor conductors of heat.

Metals are good conductors of electricity. That is why, the wire that carries current has a coating of polyvinylchloride (PVC) or a rubber like material.

Metals are sonorous.

There are very few non-metas as compared to metals.

Examples of non-metals are oxygen, sulphur, iodine and carbon etc.

The non-metals are either solids or gasses except bromine which is a liquid.

At room temperature, all metals except mercury are solids. 

Metals have high melting points, but gallium and caesium have low melting points. If you hold these two metals in your palm, they will melt. 

Iodine is a non-metal but it has a luster.

Carbon is a non-metal that can be found in various forms. Each different form is called an allotrope. Diamond and graphite are allotropes of carbon.

Diamond is a hardest natural substance. Its melting point is very high.

Graphite is a conductor of electricity.

Lithium, sodium and potassium (alkali metals) are so soft that they can be easily cut with a knife. They have low melting points and densities. 

Most metals produce basic oxides when dissolved in water. Whereas, most non-metals produce acidic oxides when dissolved in water.

Almost all metals combine with oxygen to form metallic oxides.

When copper is heated in air, it combines with oxygen to form black colour oxide namely copper(II) oxide. Similarly, aluminium forms aluminium oxide.

Metals oxides which react with both acids as well as bases to produce salt and water are known as amphoteric oxides. For example aluminium oxide and zinc oxide.