Chemistry Form 4 Essay

INTRODUCTIONAll the objects that exist around us argon made up of chemical substances. These objects exist an element, compound or mixture. All these objects contri merelye benefit to human kind. As time goes on, human has d bingle many researches to ensure all these chemical substances will be abundant for the use of themselves. Chapter 9 of Form 4 syllabus introduces the students with manufactured substances in industry.This is important for the students to appreciate the knowledge of chemistry that is still new for themselves. Personally, I phone that this chapter is an interesting chapter as it revealed the way of scientist produces the material around me. It also gives me new knowledges of the uses of chemical substances that I usually found in the laboratories. I hope, by culture this chapter, I will be to a greater extent interested in learning chemistry as it will help me in the future. All the equations from this chapter founder me to a greater extent understand of the p revious chapters.OBJECTIVES* Understand the manufacture of sulphuric acid.* Synthesise the manufacture of ammonia and its salts.* Understand subverts.* Evaluate the uses of synthetic polymer.* Apply the uses of glass and ceramics.* Evaluate the uses of abstruse materials.* Appreciate various synthetic industrial materials.ALLOYSARRANGEMENT OF ATOMS IN PURE METAL* Pure metal is soft and not very strong.* Atoms of pure metals drive home similar size and shape and are arranged closely but there is still space between the atoms. * When force is applied to pure metals, the atoms veer along one another easily. * This property causes pure metal to be ductile, that is, it apprize be stretched into a wire. * When knocked or hammered, metal atoms slide along one another to fill spaces between the metal atoms. * This property causes pure metal to be malleable, that is, it place be knocked or pressed into various desired shapes. gist OF ALLOYS* An alloy is a mixture of two or more metals blend in a accepted percentage. OR * An alloy is a substance make from a mixture of metal and other elements. OR * An alloy is a solid solution that contains at least one metal. Most often an alloy will contain only two or more metals, but some alloys contain one or more metals along with a non-metal. * A foreign atom (impurity atom) may be atoms of other metals or non-metals much(prenominal) as carbon and silicon. * The process of mixing atoms of impurities with atoms of pure metal by resolve is called alloying.PURPOSES OF qualification ALLOYSAlloys are made to* Increase the strength and hardness of the metal* Prevent corrosion of the metal* Improve the appearance of the metal so that it is more attractive.ALLOY PURE METAL ATOM MAIN FOREIGN ATOMSTEEL 99% IRON 1% CARBONSTAINLESS STEEL 74% IRON 18% CHROMIUM,8% CARBONBRONZE 90% COPPER 10% contributeBRASS 70% COPPER 30% ZINCPEWTER 97% TIN 2% COPPER1% ANTIMONYDURALUMIN 93% ALUMINIUM 3% COPPER3% MAGNESIUM1% MANGANESE COPPER NICKEL 75% COPPER 25% NICKELARRANGEMENT OF ATOMS IN ALLOYS* slag atoms which are mixed may be larger or atrophieder than atoms of pure metal. * Impurity atoms fill the empy spaces between the atoms in pure metal. * Impurity atoms can prevent the layers of metal atoms from sliding along one another easily. * Due to this, an alloy is harder, stronger, less ductile and less malleable than its pure metal.EXPERIMENT TO equalise THE HARDNESS OF AN ALLOY AND A PURE METALEXPERIMENT TO COMPARE RATE OF RUSTING BETWEEN IRON, STEEL & STAINLESS STEELSOME EXAMPLES OF ALLOYS, ITS art object, PROPERTIES AND ITS USESALLOYS COMPOSITION PROPERTIES USES OF ALLOYSCARBON STEEL 99% IRON1% CARBON HARDSTRONG * FRAMEWORK OF BUILDINGS & BRIDGES * FRAMEWORK OF HEAVY MACHINERY & BODY OF VEHICLES STAINLESS STEEL 74% IRON18% CHROMIUM8% NICKEL SHINYSTRONGRESIST RUSTING * making CUTTLERY & KITCHEN WARE MAGNALIUM 70% ALUMINIUM30% MAGNESIUM LIGHTHARDSTRONG * MAKING AIRCRAFTS PEWTER 97% TIN3% COPPER, ANTIMONY LUSTROUSST RONG * MAKING MUGS, CANDLE STICK & SOUVENIERS SOLDER 50% TIN50% LEAD HARDSHINYLOW MELTING POINT * MAKING OF SOLDER FOR electricalAL WIRES CUPRO-NICKEL COPPER, NICKEL.% ACCORDING TO COLOUR HARDSHINYRESIST CORROSION * MAKING COINSPOLYMERSMEANING OF POLYMERS* Polymers are long chains of molecule made from combinations of many small molecules. OR * Polymers can be defined as large molecules composedof numerous smaller, repeating units known as monomers which are joined by covalent bonds. * midget molecules that combine to form polymers are called monomers. * Polymerisation is a process of combining monomers to form a long chain of molecules.polymerisationpolymer monomer* Polymers can be divide into two typesa) Natural polymerb) Synthetic polymerNATURAL POLYMER* A natural polymer is a polymer that occurs naturally.* Natural polymers are normally made by living organisms. NATURAL POLYMER MONOMERS ( small molecules )RUBBER ISOPRENECELLULOSE GLUCOSESTARCH GLUCOSEPROTEIN AMINO ACIDNUCLEIC ACID NUCLEOTIDESSYNTHETIC POLYMERS* Synthetic (artificial) polymers are man-made polymers that are produced from chemical compounds through polymerization. * Synthetic polymers are employ widely in daily life.* Some examples of synthetic polymer and their monomer and their uses.TYPES OF POLYMER MONOMER USESPOLYTHENE ETHENE * MAKE BUCKETS, PLASTIC BAGS, RAINCOATS, FILMS, BOWLS & RUBBISH BINS. POLYVINYL CHLORIDE (PVC) CHLOROETHENE ( Vinyl Chloride ) * MAKE WATER PIPES, ELECTRIC CABLES, MATS, VINYL RECORDS & CLOTHES HANGERS POLYPROPENE PROPENE * MAKE ROPES, BOTTLES, CHAIRS, DRINK CANS & CARPETS PERSPEX METHYL-2-METHYLPROPENOATE(Methyl methacrylate ) * MAKE CAR WINDSCREENS, AIRPLANE WINDOW PANES & SPECTACLE LENSES (optical instruments) NYLON ADIPIC ACID & HEXANEDIAMINE * MAKE ROPES, CURTAINS, STOKINGS & CLOTHES POLY cinnamene STYRENE * MAKE PACKING BOXES, BUTTONS & NOTICEBOARDSEFFECTS OF THE DISPOSAL OF ITEMS MADE FROM SYNTHETIC POLYMERS ON THE ENVIRONMENT1. Synthetic polymers are not biodegradable (not decomposed by microorganisms ). 2. The careless organization of items made from synthetic polymers such as plastic causes environmental pollution. 3. The effects of burning & careless disposal of items made from synthetic polymers on the environments are as followsa) Burning of synthetic polymers* Releases pollutants that endanger health such as smoke, gases that are smelly, poisonous & corrosive such as sulphur dioxide, pollutants that cause acid come down & the greenhouse effect.b) Careless disposal of synthetic polymers* Spoils the beauty of the environment* Causes flash floods during heavy rainfall* Endangers marine life like turtles that accidentally eat polymers such as plastic as its food.4. The best way to manage utilize items made from synthetic polymers is to recycle them. 5. Plastics that are biodegradable can be used instead to reduce environmental pollution.GLASS AND CERAMICS* The main component of both glass and ceramic is silica or silicon dioxi de, SiO2, which is obtained from sand. * Both glass and ceramic have the same properties as follow a) Hard and brittleb) Inert to chemical reactionsc) Insulators or poor conductors of heat and electricityd) Withstand compression but not stretchinge) Can be easily cleanedf) Low cost of production* 3 main differences between glass and ceramic* Glass can be heated until molten repeatedly but not ceramics * Glass is usually transparent whereas ceramics are not* Glass has a lower run point than ceramicsUSES OF GLASSUSES OF CERAMICTYPES OF GLASSa) FUSED SILICA GLASSb) SODA-LIME GLASSc) BOROSILICATE GLASSd) LEAD CRYSTAL GLASSCOMPOSITE MATERIALS* Composite materials are produced from the combination of two or more different compounds such as alloys, metals, glass, polymers & ceramics. * The characteristics of the produced material are much more superior than those original components. * Several examples of tangled materials & their uses are a) Reinforced concrete* Made from a mixture of c ement, gravel, sand, water, iron or steel to produce nets, rods or bars. * Strong, high tensile strength & showy* Construction material for buildings, bridges, highways & damsb) Fibre glass* Made from silica, SiO2, sodium carbonate, Na2Co3, and calcium carbonate, CaCo3 * Good insulator of heat & electricity* Used to make protective clothe for astronauts & firefighters.c) Fibre optics* Made from glass, copper & aluminium* Enables information to be transmitted in light form at high speeds (speed of light) * Used in the sphere of communications to make electrical cables and in the field of medicine to observe internal organs without performing surgery.d) Ceramic glass* Produced by exposing glass that contains certain amount of metals to ultraviolet rays & heating it at high temperatures. * Withstand heat* Used to make cooking materials & rocket headse) Photochromic glass* Produced from molten silica that is mixed with a little silver chloride, AgCl * Dark in colour when exposed to br ight light ( ultraviolet ray ) & bright when in the dark. * Used to make opticl lenses & glass windows (windshields) of certain vehicles.Comparing the Properties of Fiber Glass with its original componentsThe process of making glass and fiberglassMost glass is a mixture of a substantial amount of silica that derived from fine white sand or pulverized sandstone, combined with smaller amounts of an alkali like soda (sodium bicarbonate) or potash to decrease its melting point, and lime (from limestone) to help stabilize the mixture and eventually make the glass vigorous and water-resistantWhereasAt the most basic level, a strand, or fiber, of glass, can be formed bytaking molten glass (made by melting silica sand, limestone, and soda ash, along with recycled glass) and forcing it through a small hole. Commercial fiberglass production engages a platinum bushing with up to three thousand holes in it, creating three thousand fibers at a time. Even though glass is brittle, these fibers ar e pretty flexible, because they are so thin.Advantage of using Photochromic glass in the making of spectaclesPhotochromatic lenses are trigger by UV radiation. Thus it will darken up the glasses so that it can prevent our eyes from direct lights which leads to retinal damages or Photophobia.Other than that , Photochromic lenses are great for those that wear eyeglasses, who can not wear shades unless they are prescription. With photochromic lenses, we can carry just one pair of sunglasses or goggles for all day and even nightREFERENCE* http//www.chemistrymodule.blogspot.com/* http//www.ehow.com/facts_5727690_meaning-alloy_.htmlixzz2VQ7Mc4k3http//www.bing.com/images/search?q=fused+silica+glass&view=detail&id=2D0945BBDD1229AD3B5B4C431D552902CB8C2FB4&first=31&FORM=IDFRIRhttp//chem2u.blogspot.com/