THE VARIETY OF RESOURCES ON EARTHBy the end of this chapter, you should be able to :# know the different resources on earth# understand elements, compounds and mixture# appreciate the importance of variety of Earths resources

AirWaterSoilLiving organismsMineralsFossil fuel

The various resources on earth

The various resources on earth we need and use.Water, air , soil and living organisms are four important basic resources. These sustain plant & animal (including human) life.

waterWater is very important basic resource. live & grow.Living processes70% of the Earths surface.

The important of water to human beings & animalsDissolves & transports digested food to all parts of the body.Transport oxygen Blood is made up mostly of waterImportant in excretion dissolves & gets rid of waste material.Controls body temperature

The bodies of most living organisms contain a high percentage of water.60% - 95% of body weight of living organisms is made up of water

jellyfish96%pineapple85%Human being70%fish68%

Keep the lungs moist- necessary for the exchange of gasesDilutes blood- flow to all parts of the bodySupports & maintains the body shape of invertebrate & helps invertebrate to move. (Amoeba, earthworm, leeches)Daily activities- cooking, washing, mining, transportWithout water a person will die of dehydration

Important of water to plants:The germination of seedsHelping plant cells to keep their shapeCooling plants through the process of transpirationDissolving & transporting mineral salts from the root to other parts of the plantPhotosynthesisgrowth

AIRAir is a mixture of gases- nitrogen, oxygen, carbon dioxide, rare gases & water vapour.Oxygen is needed by all living things for respiration.During respiration oxygen is used to oxidise food for release energy that are needed to carry out all activities.

Oxygen also needed for combustion. Fuels will not burn without oxygen. Burning produces carbon dioxide, water vapour, heat energy & light energy.Carbon dioxide is used in photosynthesis in plants to make their own food .Oxygen are release during photosynthesis. Therefore, photosynthesis is important to maintaining the oxygen & carbon dioxide contents in air.

photosynthesisCarbon dioxideoxygencombustionrespirationThe gases used in photosynthesis, respiration & combustion

SOILMade up of small bits of rock & decayed organisms.Contains water, air, humus & mineral salts.Habitat for many plants & animals.All green plants are dependent on soil for their supply of water & essential mineral salts, as well as the air needed for the respiration of their roots.

Humus is among the richest & darkest of soils.An organic substance that consist of dead organic matter derived from plants & animals.Necessary for the growth of healthy plants.Mineral salts dissolve in soil water, these are absorbed by plant roots.Necessary for plants grow well.Example : phosphates, nitrates, calcium, magnesium & potassium.

Soil is needed for the formation of fuels such as petroleum, natural gas & coal.Human beings use soil for many purposes, such as: (a) the construction of building (b) agriculture (c) making ceramics, glass, cement & bricks (d) mining metals, mineral salts & chemical substances

Living thingsPlants & animals are basic resources for human beings. They provide us with:FoodClothesBuilding materialsfuel

FoodHuman beings need food to obtain energy . This energy is needed to do work, to grow & maintain health.

Plants / animalsType of foodCabbage, mustardvegetableGinseng, quinineMedicineOil palm treeMargarine, oilFishMeat, oilChickenMeat, eggGoatMeat, milk

clothesWe need clothes to keep warm. Clothes protect us from cool weather & rain.

Plants / animalsType of clothesCottonShirtsLatexShoes, glovesPandanus (screw pine)HatWoolThick clothingSilkwormsBlouses, shirtsCrocodile skinShoes, bags, belts

Building materialWe need building materials for building & making tools & furniture

Plants / animals building materialsproductRattanFurniture, basketsNipah palmRoofsTeakHouses,bridges,furnitureBambooRaftsBuffalo & camel skinTents

FUELWe need fuel for cooking, to keep warm, supply light, run our vehicles & work machinery

Plants / animalsFuelMangrove treesFirewood, charcoalPlant remainsCoalPalm oilOil for lampPlant & animal remainsPetrol, kerosene, diesel, natural gaswhaleLamp oil

ELEMENTS, COMPOUNDS & MIXTURE

ElementsAn elements is the simplest form of matter.It cannot be broken down into two or more simpler substances by chemical or physical means.An element can be made up of one type of similar atoms. A group of similar atoms is known as a molecule. Copper moleculeOxygen moleculeOxygen is the element that is found the most on earth.

Elements can be classified as metals & non-metals.All metallic elements are solid states at room temperature,except mercury.Solid state- aluminium, tin, silver, potassium, cooper, iron.Liquid state- mercury

non-metallic elements exist in solid, liquid & gaseous states at room temperature.Carbon, iodine & sulphur solidBromine liquidOxygen, Chlorine, Hydrogen & Nitrogen - gas

Differences in physical characteristics of metal & non-metal

MetalDifferences Non-metalShiny Surface propertyDull Malleable Malleability Not malleableDuctile Ductility Not ductile High melting pointAbility to meltLow melting pointGood conductorConductivity of heatPoor conductorGood conductorConductivity of electricityPoor conductor ( except carbon & silicon)

Properties of metals and their uses

Metals Physical propertiesUses Copper Good conductor of electricity & heatStrong & does not corrode easilyMaking electrical wires and cooking utensilAluminiumGood conductor of heatDuctile & malleableLow density (light) & strongMaking cooking utensilMaking cables, aluminium foil, construction frames & aircraft

Metals Physical propertiesUses Iron hard, strong, does not melt easilyMaking steel, machinery, bridges, , machines & engineMercury Shiny liquid & good conductor of heatLiquid in thermometerGold / silvershiny, ductile, malleable & does not corrode* Making jewellery & ornaments

Uses of non-metals

Non-metalUses Carbon Charcoal is a type of carbon that can be used as fuelBlack lead is made of carbonSulphur Sulphuric acid ( a chemical) is produced using sulphurSulphur is an important component in fertilisers

Non-metalUses Chlorine * Chlorine is added to drinking water & swimming pools as a steriliser to kill microorganisms. Helium *Light & not explosive , suitable fill in balloons and lamp advertising Diamond * hard, cutting glass & stones, in jewellery

CompoundsA compound is formed when two or more different elements combine chemically.Compounds are formed through chemical reactions.The properties of a compound are different from those of their constituent elementsA compound becomes an entirely new substance.

Examples of compounds are iron rust (iron oxide), magnesium oxide, carbon dioxide and copper sulphate.The smallest possible particle of a compound is a molecule.A compound may be separated into its elements by using electricity ( a chemical process). The process in which this occurs is called electrolysis.

Water1 atom oxygen & 2 atoms hydrogenHydrogen chloride1 atom hydrogen & 1 atom chlorineAmmonia1 atom nitrogen & 3 atoms hydrogenMethane1 atom carbon & 4 atoms hydrogen

Common compounds

Compound Element presentState at room temperatureCarbon dioxideCarbon, oxygenGaseous Ammonia Nitrogen, hydrogenGaseous Water Hydrogen, oxygenLiquid Sulphuric acidHydrogen, sulphur, oxygen Liquid Rust Iron ,oxygenSolid Sand Silicon, oxygenSolid

Mixture A mixture is a substance that consists of two or more substances which are not joined together chemically.There is no chemical reaction in the formation of mixtures.A mixture of metals is known as an alloy.The constituents of a mixture keep their own original properties which are unchanged.A mixture may consist of elements, compounds or both.

Mixture +=Element P Element QMixture P and Q

Differences between compounds and mixture

Compound Differences Mixture Through chemical reactionFormation Through physical methodsHeat is absorbed or releasedEnergy changeNo heat changeNew substance formedFormation of new substanceNo new substance

New properties are formedProperties of componentsProperties of components remainRatio of components is fixedComposition Ratio of components is not fixedChemical processesSeparation methodsPhysical processes

Separation of mixtureComponents of a mixture can be separated using these physical methods;Using a magnetFiltration Distillation Evaporation Using separating funnelSieving Sublimation

ELEMENT / UNSUR+=1 ATOM1 ATOMMOLECULESangat kecil dan tidak boleh dipecahkan lagi kepada saiz yang lebih kecil.Terdapat dalam 2 kategori : logam dan bukan logam

Compounds / sebatian +=1 ATOM BIRU2 ATOM MERAHCOMPOUND+=

2 atau lebih atom yang berlainan jenis bergabung secara kimia dan membentuk bahan baru.Dapat diasingkan balik kepada bentuk asal secara elektrolisis sahaja.Elektrolisis proses

Mixture / campuran+=2 atau lebih atom yang berlainan jenis bergabung secara fizikal dan tidak membentuk bahan baru.Dapat diasingkan balik kepada bentuk asal secara proses fizikal.Ia mempuyai sifat asal bahan tersebut.

Preservation and conservation of resources on earthThe resources on Earth must be preserved and conserved from change and destruction.The way to preserve and conserve earths resources :# Recycling resources old mining land can be used for housing and agriculture# controlling air pollution avoid open burning of rubbish# Recycling substances glass, tin, plastic containers & old newspaper

# Use of substitutes replacing the use of substances like metals with other materials like plastic# Keeping forest reserves using up unfinished exercise books as note books and recycling paper are ways to reduce the felling of trees# Conserving water not wasting water to prevent water shortage # using resources efficiently and intelligently

I hope all of you understand and please read all your note and other references book for more information.From : your science teacher Pn. Ainun Zuraiha bt. Alias.