Properties of Metals

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Metals and their properties.

They are naturally occurring.

pure metals are elements

there are about 68 of them from 90 naturally occurring elements.

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Physical Properties of metals

Physical Properties of metals: They also do vary within each metal. For example, gold is a better conductor than tungsten and silver is the best conductor of heat and electricity. Metals generally have the same physical properties because they have the same atomic structure and are elements.

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Chemical properties of Metals: Reaction with oxygen

There are a variety of ways in which metals react to chemical change.

Chemical properties of metal is how they change when mixed with a chemical.

2 types of main reaction: Reaction to oxygen and reaction to water.

Reaction with oxygen:

Oxygen makes 21% of air so it is very common for metals to react with oxygen.

A common example is rusting which can be described as iron reacting with water and air to produce a reddish-brown substance called rust which is Iron Oxide.

Metals also tend to lose their lustre when placed outside for too long.

Iron oxide is a complex chemical compound with different properties to oxygen and water.

Rust is different in colour and lustre to iron.

Rust is flaky and so could cause the whole iron structure to flake and grow weak and collapse eventually.

Aluminium oxide:

When left out for too long, aluminium which is shiny-grey in colour changes to whitish-pale grey due to the reaction with oxygen,.

Aluminium oxide creates tough coating and prevents further reaction of the metal with oxygen and water

this is the reason why aluminium structures do not crumble like iron structures.

White flame

Some metals, including aluminium reacts with heat or oxygen to produce a brilliant white flame.

Rea

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Chemical properties of metals:Reaction with water

Sodium reaction with water:

Sodium has to be artificially extracted from a compound it forms.

When sodium metal is mixed with water, it fizzes violently and produces sodium hydroxide solution and hydrogen gas.

The sodium hydroxide stays dissolved in the water

Hydrogen gas is given off as gas.