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Descrição
FlashCards por ManishaBhaker78, atualizado more than 1 year ago
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Criado por ManishaBhaker78
mais de 8 anos atrás
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| Questão | Responda |
| What are the main uses of LIMESTONE / calcium carbinate. And is it reactive? | •good for making into blocks to make buildings with •like cathedrals • yes it is reactive |
| What is the symbol arrangement for calcium carbonate | CaCO3 |
| What is thermal decomposition | When one substance changes into 2 other substances when it is heated |
| What 2 things react to get calcium hydroxide? | Calcium oxide + water |
| How is calcium hydroxide used to test for carbon dioxide? | 1) Make solution of lime water (pour calcium hydroxide in water. 2) and bubble gas through it 3) The solution will turn cloudy if there is carbon dioxide present 4) The cloudiness is caused by the formation of calcium carbonate |
| How do you make cement out of lime stone? | Heat powdered limestone in a kiln with clay |
| What do you mix together to make mortar? What is mortar? | Cement + sand + water (The stuff you stick bricks together with ) |
| How do you make concrete | sand + aggregate (water and gravel) |
| What does quarrying limestone do to the landscape? | • destroys habitats • makes a lot of noise and dust (blasting rocks) • it gets transported away in BIG lorries ( noise + pollution ) |
| How is limestone a good thing? | • provides people with houses + roads • dyes, paints, medicine (made using chemicals from limestone) • neutralises lakes, acidic soil • used in powerstation chimneys to neutralise sulfur dioxide • provides jobs • brings more money in to the local economy |
| Name some pros and cons of limestone | Pros: • widely available • cheaper than granite answer marble • doesn't mold / rot Cons: • low tensile strength • can cracking |
| What is a metal ore | A rock which contains enough metal that makes it worthwhile to extracted metal from it. |
| What are the 2 methods of extracting metal from their ores | Chemicaly : ELECTROLYSIS • (SPLITTING WITH ELECTRICITY ) reduction through carbon : When an ore is reduced oxygen is removed from it. (The position of of the metal on the reactivity series determines whether it can be extracted by reduction of carbon |
| In the reactivity series what happens to metals above and below carbon ( when being extracted)? | Metals above carbon are extracted using electrolysis (more expensive) Metals below carbon are extracted by reduction of carbon eg: • Iron oxide is reduced in a blast furnace to make iron |
| What can carbon do to metals less reactive then itself | Take oxygen away. |
| Describe what a displacement reaction is? | •When the more reactive metal bonds more strongly to the non-metal bit of the compound • and pushes out (kicks out) the less reactive metal |
| Give an example of a displacement reaction | Copper sulfate + iron -> iron sulfate + copper Here scrap iron is used to displace copper from solution |
| What ore is in short supply and what are the name of two new methods of extracting the short supply metal? | • copper rich ores are in short supply • the demand for copper is growing • two new methods are: > bioleaching > phytomining |
| Explain what bioleaching is | Bioleaching : • this uses bacteria to separate copper from copper sulfide • the bacteria get energy from the bond between copper and sulfur • separating copper from the ore I the process • the leachate contains copper which can be filtered out. |
| Explain what phytomining Is | Phytomining: • involves growing plants in soil that contain copper • the plants can't get rid or use the copper so it build up in the leaves • the plants then get harvested, dried and burned Inot a furnace • copper is then collected from the ash left in the furnace. |
| What are the good and bad things about metal extraction | Good : • useful products are made • provides local people with jobs • brings money into the area • improves transport and health Bad : • cause noise • scarring the landscape • loss of habitat some • deep mine shafts are dangerous for a long time after the mine has been abandoned |
| Why is recycling metals so important? | Because : • Mining and extraction is too expensive • recycling metals only uses a small fraction of the energy needed to mine and extract new metals • energy don't come cheap so it save money • fossil fuels are running out so it's important to conserve them |
| What are the basic properties of metals | • strong • hard • can be bent into different shapes • great at conducting heat • great at conducting electricity well |
| Name the unique properties of : copper : aluminium : titanium | COPPER - • good conducter, hard, strong, CANNOT BE BENT, it doesn't react with WATER ALUMINIUM - • Corrosion resistant, low density, pure aluminium isn't strong ( but forms strong alloys) TITANIUM - low density, very strong, corrosion resistant |
| What is the definition of an alloy | a metal made by combining two or more metallic elements, to give greater strength or resistance to corrosion |
| Why is pure iron so bendy ( mention it's arrangement) | • It has a regular arrangement of identical atoms • the layers of atoms can slide over each other • making the iron soft and easy to shape |
| What can pure iron be used for? | Handy for making ornamental railings ( but nothing else becoz it's too brittle ) |
| What are the properties of an alloy? | • different atoms have different sized atoms • so when eg carbon is mixed with pure iron • this will upset the latest of pure iron atoms • making it difficult for the atoms to slide over each other • resulting in a harder metal (alloy) |
| What is crude oil? | Crude oil is a mixture of hydrocarbons |
| What are the steps of separating crude oil in a fractionation column? | • Hot at the bottom and cool at the top. • crude oil is vaporised •Substances with high boiling points condense at the bottom and substances with low boiling points condense at the top. • fractional distillation works because the different substances in the mixture have different boiling points. |
| What happens to the molecules of crude oil as the heat decreases | The molecules get smaller because the bonds are being being broken |
| Is crude oil mainly alkAnes or alkEnes? | ALKANES |
| Name four alkAnes and there formulas | • METHANE - CH4 • ETHANE - C2H6 • PROPANE - C3H8 • BUTANE - C4H10 |
| What the basic trends of alkanes | THE SHORTER THEY ARE THE: • more runny the hydrocarbon is • the more volatile they are (turn into to gas at lower temps) • more flammable |
| What is crude oil used for | • Most modern transport is fueld by it. • also burned in central heating systems in homes, powerstations o generate electricity. |
| As well as fuel what other thing does crude oil providd | It provides a raw material for making various chemicals including PLASTICS. |
| What is the problem with using crude oil as a fuel for modern life? | • one day it is going to run out As it is a non-renewable source of energy |
| List some renewable sources of energy and their pros and cons... | • wind, - no air pollution, not reliable • solar, - no pollution, not reliable • tidal, - no pollution, not reliable |
| Why is crude oil not the environments best friend? | • oils spills • animals can get poised if they get covered in it • you need to burn it to get energy • this results in - global warming - acid rain -global dimming |
| What gas can cause acid rain and how | - Sulfur dioxide • when the Sulfur dioxide from factories and cars mix with clouds • it forms dilute sulfuric acid • this then falls as acid rain |
| What does acid rain do to the environment? | • causes lakes to become acid • animals and plants die as a result • kills trees • damages limestone buildings • ruins stone statues |
| You can reduce acid rain by reducing sulfur emissions (give some examples) | -By reducing the amount of fossil fuels that are used - putting gas scrubbers in power stations to take out harmful gases before they release there fumes into the atmosphere |
| How does increasing carbon dioxide cause climate change | - it has caused the average temperature of earth to rise causing global warming - causing the ice caps to melt - flooding - changing of rain family. Like patterns |
| What is global dimming | Its a theory that people think that sunlight on earth is being reduced • particles of soot and ash that are produced when fossil fuels are burnt • these particles reflect the sunlight back into space • or contribute to produce more clouds that reflect the sunlight back into space |
| Why don't some scientist believe the change is real | Because they think it is an inaccurate recording of equipment |
| Name three alternative fuels that are being developed and some pros and cons | ETHANOL- [Pro] - carbon neutral [Cons] - engines need to be converted - food prices will rise as a lot of crops for ethanol will be grown BIODIESEL- [Pros] - carbon neutral - less suffer dioxide [Cons] - expensive to make - increase in food prices HYDROGEN GAS- [pros] - it's clean (only produces water) [Cons] - need a special expensive engine - not widely available - hard to store |
| What does cracking mean? | Splitting up long chain hydrocarbons |
| Products from fractional distillation are cracked - what are they useful for? (Diesel is cracked) | Fuels, Petrol for cars Paraffin for jet fuel And ether for plastics |
| Describe the chemical reaction: cracking - How it is done and what is needed | : it's a thermal decomposition reaction ( breaking molecules down by heating get them • heat the long chain of hydrocarbs to vaporise it • the vapor is passed over a aluminium oxide CATALYST • 400°- 700° The long chain molecule is split apart "cracked" of the surface of the specks of catalyst. |
| What bond does ALKENES | C=C (Double bond) |
| How can you test for an alkEne | By adding bromine water • the alkEne will decolourise it • Turning it from orange to to colourless • this is because the double bonds have opened up and formed bonds with the bromine |
| How can ethanol be made and why will it eventually become expensive | •Produced from crude oil • crude oil is a non-renewable recourse • it will soon run out • making it become expensive in the future |
| How else can ethanol be made? | From renewable resources like: - Sugar • this is converted into ethanol using yeast |
| What are the advantages and disadvantaged of making ethanol through sugar | Advantages • it's a major all over the world *especially in poor countries • ethanol produced this way can produce cheap fuels in countries that don't have many oil reserves disadvantages • ethanol throughthis process isn't very concentrated • need whisky distilleries to make more stronger • then needs to be purified |
| What can alkenes be used to make? | POLYMERS |
| How is a polymer made | Joining together lots of small alkene molecules. This then forms big molecules. These long chain molecules are called molecules. |
| What do fruits and seeds contain a lot of? | They contain a lot of OIL |
| How do we extract oil from plants | • plant material is crushed • press the crushed plant material between metal plates • and squash the oil out |
| What are vegetable oils used in and what do they contain? | • they are used in food • they contain vitamin E • and essential fatty acid our body needs for many metabolic processes. |
| What benefits do vegetable oils have in cooking? | • has a higher boiling point then water • cook food at higher speeds • different flavours • using oil to cook food, increases the energy we get from eating it. |
| How come vegetable oils can be used to produce fuels | • rapeseed and soybean oil can be processed and turned into fuel • because they prove a lot of energy • biodiesls are made from vegetable oils • it has the similar properties as ordinary diesel fuel |
| What kind of bond does: • unsaturated oils • monounsaturated • polyunsaturated | • unsaturated oils = double bonds between some of the carbon atoms • monounsaturated = one c=c double bond somewhere • polyunsaturated = more than one c=c double bond. |
| How can you hydrogenate unsaturated oils? | • unsaturated oils are liquid at room temp. • by reacting them with hydrogen in the presence of a NICKEL CATALYST at 60° • the hydrogen reacts with the double bonded carbons and opensee out the double bond |
| What uses do hydrogenated oils have? | • they are solid at room temperature • because they have a higher melting point Making them easier to spread and for baking |
| What is the bad thing about hydrogenating oils? | You conatin a lot of trans-fats which are really bad for Partially hydrogenating oil produce a longer shelf life Plus it's cheaper |
| What is the difference between saturated and unsaturated fats and the effect on health | • saturated fats are less healthy then unsaturated fats • saturated facts increase the amount of cholesterol in the blood • can lead to heart disease BUT • naturally unsaturated oils like olive oils and sunflower oil REDUCE THE amount of blood cholesterol |
| What are the 2 types of emulsions | • oil in water emulsion • water in oil emulsion |
| What is an emulsifier? | : an apparatus used for making an emulsion by stirring or shaking a substance. |
| What does hydrophilic And hydrophobic mean | • hydrophilic (head) - attracted to water • hydrophobic (tail) - attracted to oil |
| How does an emulsion work | • when you SHAKE oil and water together they don't mix • BUT with an emulsifier ... - the hydrophilic head sticks to the water molecules - and the hydrophobic head cosies up to the oil molecules |
| What are the pros and cons of using emulsifiers? | PROS • stop separation • longer shelf life • lower fat with good texture (good for the company) CONS • Some people are epileptic to certain emulsifiers • (EGGS) |
| Who invented the theory of continental drift | ALFRED WEGNER |
| What was the evidence that supported wegners theory? | • the continents fit together like a jigsaw ( Africa and south America) • similar fossils on opposite sides of the ocean • matching layers In rocks • fossils of tropical plants found in artic islands (present climate would have killed them off) |
| Why was his theory not accepted for many years? | • inaccurate data • he wasn't a proper geologist (studied astrinomy) |
| Describe the arrangement of the earth and their movement | • CRUST - thin layer surrounded by the atmosphere • MANTLE - has all properties of a solid but flows very slowly - radioactive decay takes place in the mantle - causing it to flow in convection currents - inner and outer core we think is made of iron and nickel |
| How do earthquakes and volcanoes happen? | When the tectonic plates have a sudden movement Often occur at the boundaries |
| Why can't scientists predict if a volcano or earthquake we will happen? | Because they don't have the right technology to pick up any plate movement Before an eruption of a volcano the chambers get filled with molten Roch making the ground to budget - resulting in a mini earthquake - but sometimes the rock can cool so it can be a false alarm... |
| Tell me about the evolution of the atmosphere | 1) • atmosphere was hot • eventually cooled Nd volcanoes erupted • co2, methane, water vapour, ammonia, was released • these the condensed and formed the oceans 2) • green plants and algae where happy in the co2 filled atmosphere • a lot of co2 was absorbed by the oceansame and not By plants • they photosynthesised and produced o2 3) • the build up of oxygen killed off some early organisms • but allowed other organisms to evolve and flourish • oxygen then created ozone layer blocking off harmful rays from the sun • enabling more complex organisms to evolve (us eventually) |
| Explain the primordial soup theory? | THIS THEORY STATES THAT ONCE OUR ATMOSPHERE CONSISTED OF : nitrogen, hydrogen, ammonia, methane • lightening stuck causing a chemical reaction • causing the formation of ammonia • the amino acids collected in a primordial soup • which life crawled not of eventually • the amino acids eventual produced organic matter • evolved into simple organisms |
| Who did an experiment to prove the primordial soup theory was correct | MILLER AND UREY |
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