Transcript Land and its resources TITLE INTRODUCTION

TITLE
LAND AND ITS RESOURCES
INTRODUCTION
The Earth crust is a thin layer on the outer section of
the Earth. There are various mineral in the earth crust.
Look around you. Buildings, pencil lead, tap water,
even the sand you step on, all come from mineral in
the Earth crust. Minerals are much used in the building
industry, transportation, industry, agriculture, and as
natural fuel resources.
WHAT YOU WILL LEARN ?
Analyse the various minerals in the earth crust
 Understand the reactions between metal and non-metals
 Understand silicon compounds
 Analyse natural fuel resourses and their importance
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VARIOUS MINERALS IN THE EARTH CRUST
Minerals are elements or chemical compounds are naturally present
in the Earth crust.
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Examples of common minerals are gold, jade, limestone and tin ore.
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Minerals exist in the form of element or compound
Examples of natural mineral elements are gold, silver(argentum),
platinum and mercury
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Carbon and sulphur are two type of non-metal mineral element that
exist naturally
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A FEW TYPES OF NATURAL MINERALS, MINERAL CONTENT AND ELEMENT THAT FORM IT
natural
minerals
Type of ore
Mineral
content
Element in the
mineral
Bauxite
Aluminium ore
Aluminium
oxide
Aluminium
and oxygen
Cassiterite
Tin ore
Tin oxide
Tin and
oxygen
Hematite
Iron ore
Iron oxide
Iron and
oxygen
Magnetite
Magnesium
oxide
Magnesium
carbonate
Magnesium,
carbon and
oxygen
Malachite
Copper ore
Copper
carbonate
Copper,
carbon and
oxygen
Galena
Lead ore
Lead sulphide
Lead and
sulphur
Iron pyrite
Iron ore
Iron sulphide
Iron and
sulphur
GOLD
JADE
QUARTZ
LIMESTONE
CHARACTERISTICS OF MINERALS
Most minerals are still in existence and have not changed in the
Earth crust because minerals are generally hard and do not dissolve in
water.
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Minerals like metal oxide and silicate normally do not decompose
when heated .
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Some minerals like metal carbonates and sulphide can be easily
decomposed by heating. The effect of heat decomposes the
compound into its elements or other compounds.
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For example :
heated
metal carbonate
metal oxide + carbon dioxide
REACTION BETWEEN METALS AND NON-METALS
A metal is an element with a surface that is shiny, ductile and can
be forged.
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Examples of metal include zinc, magnesium, sodium, iron and many
more.
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A non metal is an element with a surface that is dull and brittle
Examples of non metal include graphite ( carbon ) , sulphur, oxygen
and chlorine.
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REACTION OF METAL WITH OXYGEN
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Most metals react with oxygen to form metal oxide
metal + oxygen
metal oxide
Example :
Magnesium + oxygen
Zinc + oxygen

magnesium oxide
zinc oxide
Different metals have different reactivity with oxygen
Metals like sodium and potassium are very active and
easily combine with oxygen even though they may only be
exposed to air.
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sodium + oxygen
sodium oxide
REACTION OF METALS WITH SULPHUR
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Most metals react with sulphur to form metal sulphide
metal + sulphur
metal sulphide
Example :
Iron + sulphur
iron sulphide
Zinc + sulphur
zinc sulphide
Just like the reaction between metal and oxygen, different
metals have different reactivity with sulphur.
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SILICON COMPOUND
Silicon is the second most abundant non-metals element
found in the Earth crust.
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Silicon usually combines with other elements like metal
and oxygen to from a silicon compound.
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Silica and silicate are silicon compound
SILICA
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Silica is also known as silicon dioxide.
Silica consists of a combination of silicon and oxygen
elements in the following equation
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silicon + oxygen
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silicon dioxide(silica)
Examples of silica are sand, quartz and flint.
SILICATE
Silicate is a silicon compound that contains silicon, metal
and oxygen elements.
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Silicate is formed when silicon combines with oxygen and
metal
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silicon + oxygen + metal
silicate
Examples of silicate include clay, mica, feldspar, and
asbestos. Most ornamental stones like jade, ruby and topaz
are silicate.
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CHARACTERISTIC OF SILICON COMPOUND
Both silicon compound i.e silica and silicate, are very
stable.
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Silicon compound
(a) do not dissolve in water
(b) do not react with acid
(c) do not decompose when heated
These characteristics of silicon compounds result in their
existence as the second most abundant compound found in
the Earth crust.
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NATURAL FUEL RESOURCES AND THEIR IMPORTANCE
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Natural fuel resouces found in the Earth crust include
(a) petroleum
(b) natural gas
(c) coal
(d) wood
Petroleum and natural gas are hydrocarbon compounds
because both consist of a compound mixture that is only
formed from hydrogen and carbon elements.
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PETROLEUM
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Petroleum is a black and viscous liquid
Petroleum is formed from decayed dead sea animals and
plants that settled on the sea bed millions of years ago.
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Petroleum consists of mixture of various hydrocarbon
compounds
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These various hydrocarbon compounds can be seperated
through fractional distillation. This is because all the
different types of hydrocarbon have different boling points.
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All petroleum fraction do not dissolve in water
NATURAL GAS
Natural gas is hydrocarbon compound usually obtained
together with petroleum.
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Natural gas is used
(a) as fuel in factoriesand in the home.
(b) to make ammonia and nitrogen-based fertiliser
COAL AND WOOD
Coal is formed from swamp plants that died millions of years ago
and have been compressed by layers of earth on top of it
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High pressure and temperature that act on these plants change
them into coal
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Uses of coal include
(a) generating electric energy in thermoelectric generating stations
(b) warming the house in winter
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Uses of wood include
(a) being turned into pulp to make paper
(b) as planks used to make furniture, from the mangrove trees