Materials Natural or Man Made Natural materials can

Materials

Natural or Man Made? • Natural materials can come from living things • Natural materials can be used in their natural state Wool Leather

Natural Materials This is rubber tapping A cotton field

Natural Materials A Silkworm An Oil Rig Diamond Mining

Metals are Natural • Metals taken from ores are natural Gold Bullion Iron age tools and weapons A Silver Nugget

Synthetic (Man Made) Materials • These are materials that are not made by animals or plants or found naturally in the ground • They are made by man Rayon Fibres Nylon Toothbrush Bristles

Synthetic Materials • Plastics are man made Polystyrene Packaging Polythene Plastic Bags Polycarbonate CDs

Synthetic Materials The Delorean was made from Stainless Steel Glass is made from Sand, Soda and Limestone Bricks and Cement are man made

Raw Materials • Oil is a raw material, it can be separated into: • Diesel for cars • Petrol for cars • Kerosene for Lamps • Bitumen for laying roads • Plastic is made from Oil • These are all manufactured materials

Manufactured Materials • A raw material is found naturally • A manufactured material is the finished product that can be sold in shops • Cotton is a raw material • It is manufactured into thread and sewn to make garments e. g. socks, t-shirts etc. • Iron is a raw material • It has to be manufactured into Steel car bodies

Questions • We get Aluminium from Aluminium ore, is it a natural material? • Yes • Brass is an alloy of Copper and Zinc, is it natural? • No it is man made • Is petrol a natural or man made material? • Manufactured because it has to be removed from oil in a factory

Conductor or Insulator? • Metals conduct heat and electricity Copper electrical wire, with plastic insulator • Most non-metals are insulators Metal Saucepan conducts heat, the plastic handle insulates

Strong or Brittle? • Brittle materials break easily Glass and Porcelain break easily • Strong materials are difficult to break This Iron bridge is strong

Transparency? • Transparent means that you can see through it e. g. glass and Perspex • You can not see through opaque objects e. g. curtains, blinds • Translucent objects let some light through e. g. frosted glass

Flexible or Rigid? • Flexible materials can bend easily, without breaking • Rigid materials do not bend easily, when bent to far they break Flexi Rulers A Rigid Wooden Ruler

Hard or Soft? • Hard materials are difficult to scratch e. g. diamond, enamel and glass • Soft materials are easy to scratch and cut Diamonds are difficult to damage, they can cut through glass and metal

Other Properties • Malleable materials can be hammered into shape e. g. Lead • Ductile materials can be stretched into wires e. g. metals • Shiny materials reflect lots of light e. g. when you can see your reflection in polished cars • Dull materials do not reflect light

Questions • • What materials is used to make windows? Glass What property make it good for this job? It is transparent Why do some saws have diamond teeth? It is the hardest material on Earth Why is polystyrene used for packaging brittle materials? • It is flexible and won’t damage the materials

States of Matter • The Particle Theory states that all substances are made of tiny atoms (particles) • Substances are either a: • Solid e. g. ice • Liquid e. g. water • Gas e. g. steam

Solids • The atoms are close together, they can not move about, but are always vibrating • They are arranged in a regular pattern • Solids have fixed shape and volume (they can not be compressed)

Liquids • The atoms are quite close together, but are able to move past each other • Liquids can flow • They take the shape of their container • They can not be compressed

Gases • • The atoms are far apart The atoms are moving very quickly They fill a container They are easy to compress

Questions • • • Which state can be squeezed easily? Gases e. g. an empty bottle Which out of solids, liquids and gases can flow? Liquids Gases In which state can the atoms not move around freely? • Solids • In which state are the particles moving very quickly? • Gases

Questions • What is the process when solids change to liquids? • Melting • Liquids to solids? • Freezing • Gases to liquids? • Condensation • Liquids to gases? • Evaporation

Links • http: //www. bbc. co. uk/schools/ks 3 bitesize/s cience/chemistry/particle_model_intro. sht ml • http: //lgfl. skoool. co. uk/keystage 3. aspx? id= 64