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6 Physical Properties of Metals

Most metals have a high density because the atoms are closely packed together.

Metals are Malleable which means it can be bent, this is because the layers of atoms in a metal can slide over each other easily.

Metals are ductile which means they can be stretched, this is because the layers of atoms in a metal can slide over each other easily.

Metals are good conductors of electricity because there are free electrons present in metals that can freely move through the metal.

Metals have high melting points ( with few exceptions) this is because the attraction force between the atoms in metals is stronger, which means more thermal energy is needed to overcome these forces.

Metals can conduct heat because there are free electrons present in metals that can freely move through the metal carrying the thermal energy.

5 Chemical Properties of Metals

Most reactive metals (according to reactivity series) can react with cold water to give metal hydroxide and hydrogen gas

less reactive metals (according to reactivity series) can react with steam to give metal oxide and hydrogen gas

Most metals react with dilute hydrochloric acid to give metal chloride and hydrogen gas

Most metals react when heated in oxygen to give metal oxide

Silver and Gold usually does not react with oxygen, hydrochloric acid, or water.

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Alloys

Alloy is a mixture of 2 or more metallic or non-metallic elements to make the pure version of a metal much stronger. In pure metals, the layers of atoms can easily slide over one another but mixing another metal in it make the layers of atom irregular which prevents it from sliding thus making the metal stronger

9A

a) Ornaments are not made of pure tin because any metal in its pure form is weak and can break easily.

b) The name used for mixtures of metal is Alloy.

c)

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Ba s +2h20 l Ba(0H)2 aq + h2 g

2al s + 6 hcl | 2alcl3 3h2 g

sn s + 2h2o g | sn02 + h2