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Metals and their Properties

Metals have distinctive properties such as: 1. Electrical Conductivity

2. Good Thermal Conductivity 3. Strength

4. Malleability.

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Reaction of MetalsReaction of Metals With Oxygen:

All metals react with Oxygen. The morereactive the metal the quicker the reaction.

In the Lab the Oxygen is produced by heatingPotassium(v)Manganate.

The Brighter the glow the more the reactive the

metal. Less reactive metals produce a duller glow General Equation:

Metal + Oxygen Metal Oxide

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Metals + Oxygen (contd)

Potassium (v)Manganate

acts as a source ofOxygen when Heated

Mg metal is

placed

between two

pieces of

ceramic wool

The more active the metal the brighter

the glow

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Reactions of MetalsReactions of Metals With Water:

Only Metals above Hydrogen in the ActivitySeries react with water.

In fact only the first three react withCold water.

The remaining metals above Hydrogen must be

treated withSteam before a reaction will take place.

General Equation:

Metal + H2O Metal Hydroxide + H2

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Reactions of MetalsReactions of Metals

With Acids:Only Metals above Hydrogen in the

Activity Series react with Acids.

General Equation:

Metal + Acid Salt + Hydrogen

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Metals and Acid(contd).

PopPop

When a metal is reacted with

an Acid it produces H2 gas

which burns with a POP!

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Alloys An Alloy is a mixture of metals or metals and

other elements. Alloys are made to change the properties of the

metal e.g.to make them harder, more pleasing

on the eye or to make them more resistant to

Corrosion.

Examples are: Brass(a mixture of Cu&Zn), Gold(Au&Cu.The greater the proportion of Cu the

lower the no.of carats),Stainless Steel(Fe,Ni&Cr)

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Metal Ores

Most metals are found combined to other elementssuch as, Oxygen and Sulphur in the earths

crust.These are calledMetal Ores.

Only Gold, Silver and Platinum are found

uncombined.

As a result metals must be mined and then separatedfrom their Ores by Metal Extraction

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Extraction of Metals from their

Ores

Metals low down in the Electrochemical Seriesform weak bonds with other elements. As a

result Ores of these metals can broken up easily

to obtain the metal.

Ores of metals high up in the Electrochemical

series contain stronger bonds and thereforerequire more sophisticated and expensive

methods of Extraction

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Electrochemical Series

PotassiumSodium

CalciumMagnesium

Aluminium

Zinc

IronNickel

Tin

Lead

HYDROGEN

Copper

Mercury

StealingGold

Plates

Can be Broken by Heat alone

Separated from ore by Heating with

CHARCOAL, thus releasing CARBON

DIOXIDE.

Must be Electrolysed to release

Metal from Ore