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Chemistry Revision Notes

Chemistry 1 Revision Booklet Unit Chemistry 1 Syllabus At the beginning of each sub-section, activities are stated which develop candidates. skills, knowledge and understanding of how science works. Details are then given of the substantive contexts in which these skills, knowledge and understanding should be set. It is expected that, where appropriate, teachers will adopt a practical approach, enabling candidates to develop skills in addition to procedural knowledge and understanding. Note that objective test Chemistry 1a examines Section 11. 1 . 11. 3 and objective test Chemistry 1b examines Sections 11. . 11. 6. 11. 1 How do rocks provide building materials? The exploitation of rocks provides essential building materials. Limestone is a naturally occurring resource that provides a starting point for the manufacture of cement, concrete and glass. Throughout Unit Chemistry 1, candidates should know that atoms are held together in molecules and lattices by chemical bonds, but no detailed knowledge of the types of chemical bonding is required. Candidates should be able to interpret chemical equations in symbol form and should be able to balance equations in terms of numbers of atoms.

Candidates should use their skills, knowledge and understanding of how science works: to consider and evaluate the environmental, social and economic effects of exploiting limestone and producing building materials from it to evaluate the developments in using limestone, cement, concrete and glass as building materials, and their advantages and disadvantages over other materials. Their skills, knowledge and understanding of how science works should be set in these substantive contexts: All substances are made of atoms. A substance that is made of only one sort of atom is called an element.

There are about 100 different elements. Elements are shown in the periodic table. The groups contain elements with similar properties. Atoms of each element are represented by a chemical symbol, eg O represents an atom of oxygen, Na represents an atom of sodium. Atoms have a small central nucleus around which there are electrons. When elements react, their atoms join with other atoms to form compounds. This involves giving, taking or sharing electrons and the atoms are held together by chemical bonds. (No further knowledge of ions, ionic and covalent bonding is required in this unit. Atoms and symbols are used to represent and explain what is happening to the substances in chemical reactions. The formula of a compound shows the number and type of atoms that are joined together to make the compound. Chemistry – General Certificate of Secondary Education, 2007/8 examination hij No atoms are lost or made during a chemical reaction so the mass of the products equals the mass of the reactants and we can write balanced equations showing the atoms involved. Limestone, containing the compound calcium carbonate (CaCO3), is quarried and can be used as a building material. 34

Calcium carbonate can be decomposed by heating (thermal decomposition) to make calcium oxide (quicklime) and carbon dioxide. Carbonates of other metals decompose on heating in a similar way. Quicklime (calcium oxide) reacts with water to produce slaked lime (calcium hydroxide). Limestone and its products have many uses, including slaked lime, mortar, cement, concrete and glass. 11. 2 How do rocks provide metals and how are metals used? Metals are very useful in our everyday lives. Ores are naturally occurring rocks that provide an economic starting point for the manufacture of metals.

Iron ore is used to make iron and steel. Copper can be easily extracted but copper rich ores are becoming scarce. Aluminium and titanium are useful metals but are expensive to produce. Candidates should use their skills, knowledge and understanding of how science works: to consider and evaluate the social, economic and environmental impacts of exploiting metal ores, of using metals and of recycling metals to evaluate the benefits, drawbacks and risks of using metals as structural materials and as smart materials to explain how the properties of alloys (but not smart alloys) are related to models of their structures.

Their skills, knowledge and understanding of how science works should be set in these substantive contexts: Ores contain enough metal to make it economical to extract the metal and this changes over time. Unreactive metals such as gold are found in the Earth as the metal itself but most metals are found as compounds that require chemical reactions to extract the metal. Metals that are less reactive than carbon can be extracted from their oxides by reduction with carbon, for example iron oxide is reduced in the blast furnace to make iron. (Details of the blast furnace are not required. ) Iron from the blast furnace contains about 96% iron.

The impurities make it brittle and so it has limited uses. Removing all of the impurities would produce pure iron. Pure iron has a regular arrangement of atoms, with layers that can slide over each other, and so is soft and easily shaped, but too soft for many uses. General Certificate of Secondary Education, 2007/8 examination – Chemistry hij 35 Most iron is converted into steels. Steels are alloys since they are mixtures of iron with carbon and other metals. The different sized atoms added distort the layers in the structure of the pure metal, making it more difficult for them to slide over each other, and so alloys are harder.

Alloys can be designed to have properties for specific uses. Low carbon steels are easily shaped, high carbon steels are hard, and stainless steels are resistant to corrosion. Many metals in everyday use are alloys. Pure copper, gold, and aluminium are too soft for many uses and so are mixed with small amounts of similar metals to make them harder for everyday use. Smart alloys can return to their original shape after being deformed. The elements in the central block of the periodic table are known as transition metals. Like other metals they are good conductors of heat and electricity and can be bent or hammered into shape.

They are useful as structural materials and for making things that must allow heat or electricity to pass through them easily. Copper has properties that make it useful for electrical wiring and plumbing. Copper can be extracted by electrolysis of solutions containing copper compounds. (No details are required of the extraction process. ) The supply of copper-rich ores is limited. New ways of extracting copper from low-grade ores are being researched to limit the environmental impact of traditional mining. Low density and resistance to corrosion make aluminium and titanium useful metals.

These metals cannot be extracted from their oxides by reduction with carbon. Current methods of extraction are expensive because: ? there are many stages in the processes ? much energy is needed. We should recycle metals because extracting them uses limited resources and is expensive in terms of energy and effects on the environment. 11. 3 How do we get fuels from crude oil? Crude oil is an ancient biomass found in rocks from which many useful materials can be produced. Crude oil can be fractionally distilled. Some of the fractions can be used as fuels. Candidates should use heir skills, knowledge and understanding of how science works: to evaluate the impact on the environment of burning hydrocarbon fuels to consider and evaluate the social, economic and environmental impacts of the uses of fuels to evaluate developments in the production and uses of better fuels, for example ethanol and hydrogen. Chemistry – General Certificate of Secondary Education, 2007/8 examination hij Their skills, knowledge and understanding of how science works should be set in these substantive contexts: Crude oil is a mixture of a very large number of compounds.

A mixture consists of two or more elements or compounds not chemically combined together. The chemical properties of each substance in the mixture are unchanged. It is possible to separate the substances in a mixture by physical methods including distillation. Most of the compounds in crude oil consist of molecules made up of hydrogen and carbon atoms only (hydrocarbons). Most of these are saturated hydrocarbons called alkanes, which have the general formula CnH2n+2 Alkane molecules can be represented in the following forms: ? C2H6 ? HH 36 H C C H

HH The many hydrocarbons in crude oil may be separated into fractions, each of which contains molecules with a similar number of carbon atoms, by evaporating the oil and allowing it to condense at a number of different temperatures. This process is fractional distillation. Some properties of hydrocarbons depend on the size of their molecules. These properties influence how hydrocarbons are used as fuels. Most fuels contain carbon and/or hydrogen and may also contain some sulfur. The gases released into the atmosphere when a fuel burns may include carbon ioxide, water (vapour), carbon monoxide and sulfur dioxide. Particles may also be released. Sulfur dioxide causes acid rain, carbon dioxide causes global warming, and particles cause global dimming. Sulfur can be removed from fuels before they are burned, for example in vehicles. Sulfur dioxide can be removed from the waste gases after combustion, for example in power stations. 11. 4 How are polymers and ethanol made from oil? Fractions from the distillation of crude oil can be cracked to make smaller molecules including unsaturated hydrocarbons such as ethane.

Unsaturated hydrocarbons can be used to make polymers and ethene can be used to make ethanol. Candidates should use their skills, knowledge and understanding of how science works: to evaluate the social and economic advantages and disadvantages of using products from crude oil as fuels or as raw materials for plastic and other chemicals to evaluate the social, economic and environmental impacts of the uses, disposal and recycling of polymers General Certificate of Secondary Education, 2007/8 examination – Chemistry ij 37 to evaluate the advantages and disadvantages of making ethanol from renewable and nonrenewable sources. Their skills, knowledge and understanding of how science works should be set in these substantive contexts: Hydrocarbons can be broken down (cracked) to produce smaller, more useful molecules. This process involves heating the hydrocarbons to vaporise them and passing the vapours over a hot catalyst. A thermal decomposition reaction then occurs. The products of cracking include alkanes and unsaturated hydrocarbons called alkenes.

Alkenes have the general formula CnH2n Unsaturated hydrocarbon molecules can be represented in the following forms: ? C2H4 ? Some of the products of cracking are useful as fuels. Ethene can be reacted with steam in the presence of a catalyst to produce ethanol. Alkenes can be used to make polymers such as poly(ethene) and poly(propene). In these reactions, many small molecules (monomers) join together to form very large molecules (polymers). Polymers have properties that depend on what they are made from and the conditions under which they are made.

For example, slime with different viscosities can be made from poly(ethenol). Polymers have many useful applications and new uses are being developed, for example: new packaging materials, waterproof coatings for fabrics, dental polymers, wound dressings, hydrogels, smart materials, including shape memory polymers. Many polymers are not biodegradable, so they are not broken down by microorganisms and this can lead to problems with waste disposal. 11. 5 How can plant oils be used? Many plants produce useful oils which can be converted into consumer products including processed foods.

Vegetable oils can be hardened to make margarine. Biodiesel fuel can be produced from vegetable oils. Candidates should use their skills, knowledge and understanding of how science works: to evaluate the effects of using vegetable oils in foods and the impacts on diet and health to evaluate the benefits, drawbacks and risks of using vegetable oils to produce fuels to evaluate the use, benefits, drawbacks and risks of ingredients and additives in foods. Chemistry – General Certificate of Secondary Education, 2007/8 examination ij Their skills, knowledge and understanding of how science works should be set in these substantive contexts: Some fruits, seeds and nuts are rich in oils that can be extracted. The plant material is crushed and the oil removed by pressing or in some cases by distillation. Water and other impurities are removed. Vegetable oils are important foods and fuels as they provide a lot of energy. They also provide us with nutrients. Oils do not dissolve in water. They can be used to produce emulsions. Emulsions are thicker than oil or water and have many uses that depend on their special properties.

They provide better texture, coating ability and appearance, for example in salad dressings and ice creams. Vegetable oils that are unsaturated contain double carbon carbon bonds. These can be detected by reacting with bromine or iodine. Vegetable oils that are unsaturated can be hardened by reacting them with hydrogen in the presence of a nickel catalyst at about 60 °C. The hydrogenated oils have higher melting points so they are solids at room temperature, making them useful as spreads and in cakes and pastries. Processed foods may contain additives to improve appearance, taste and shelf-life.

These additives must be listed in the ingredients and some permitted additives were given E-numbers. Chemical analysis can be used to identify additives in foods. Artificial colours can be detected and identified by chromatography. 11. 6 What are the changes in the Earth and its atmosphere? The Earth and its atmosphere provide everything we need. The Earth has a layered structure. Large-scale movements of the Earth. s crust can cause changes in the rocks. The Earth. s atmosphere was originally very different from what it is today. It has been much the same for the last 200 million years and provides the conditions needed for life on Earth.

Recently human activities have produced further changes. Candidates should use their skills, knowledge and understanding of how science works: to explain why the theory of crustal movement (continental drift) was not generally accepted for many years after it was proposed to explain why scientists cannot accurately predict when earthquakes and volcanic eruptions will occur to explain and evaluate theories of the changes that have occurred and are occurring in the Earth. s atmosphere to explain and evaluate the effects of human activities on the atmosphere.

Their skills, knowledge and understanding of how science works should be set in these 38 substantive contexts: The Earth consists of a core, mantle and crust. Scientists once thought that the features of the Earth. s surface were the result of the shrinking of the crust as the Earth cooled down following its formation. General Certificate of Secondary Education, 2007/8 examination – Chemistry hij Summary questions rocks and building This sheet is a summary of the work done in this chapter. Answer all the questions in the spaces provided. 1 Particles and chemicals.

Eliminate the wrong option in the following true/false questions. a) An element contains only one type of atom. b) Silver oxide is an element. c) Calcium carbonate CaCO3 contains three elements. d) The formula of calcium carbonate contains six atoms. e) Sand and water is a mixture. f) Sand and water are hard to separate. g) Decomposition means the same as synthesis. h) CO2 contains two elements and three atoms. 2 The decomposition of metal carbonates. a) The two elements present in all carbonates are _______________ and _______________. b) Magnesium carbonate has the formula, ____________.

It is a compound because it contains more than one type of _______________ bonded _______________. When it is heated, it _____________ to give magnesium ______________ and carbon _____________________ gas. This type of reaction is called _____________________ decomposition. The gas can be tested for using _________________________ which goes ______________ if the gas is present. This question is about limestone. For each alternative, cross out the wrong answer. Limestone is calcium carbonate/calcium sulfate and has the chemical formula CaCO3/CaSO4. It is a very rare/abundant chemical and has many uses.

When it is heated in a limekiln/blast furnace it decomposes to give solid calcium sulfide/calcium oxide and the gas carbon dioxide. This reaction is an example of catalytic/thermal decomposition. One of the uses of limestone is as a building material. Also, when it is heated with sand/clay it gives cement and when it is heated with a mixture of sand/cement and sodium carbonate/sodium acetate it gives glass. true/false true/false true/false true/false true/false true/false true/false true/false 3 4 Quicklime and slaked lime. Complete the following paragraph by filling in the gaps.

Quicklime has the chemical name calcium ______________ and is formed when limestone (chemical name ____________ __________) is heated strongly. When water is added to quicklime, an ________________ reaction occurs which gives out a lot of heat energy. This reaction can be used in kits to ____________ up food or as a hand warmer. The substance formed in the reaction between quicklime and water is called ___________ ____________ and has the chemical name ___________ ______________ (chemical formula = Ca(OH)2). This chemical is used in the __________ trade where it is mixed with sand and water to form ___________ mortar.

When a lot of water is added to _______________ _________________, lime water is formed and this reacts with carbon ___________ gas to give calcium _____________ and water. The calcium ____________ is a solid and turns the lime water ________, because we get back to calcium ______________ which is what we started off with. This series of reactions is called the ____________ cycle. Balancing equations. Complete the following equations by either putting in the missing numbers or the formulae for the missing substances. Remember if the number before the formula is 1 (one) then we just leave it. ) H2 (g) + Cl2 (g) > __HCl (g) b) 2Mg (s) + O2 (g) > __MgO (s) c) __H2 (g) + O2 > __H2O (l) d) CaCO3 (s) > CaO (s) + _____ (g) e) __HCl (aq) + CaCO3 (s) > CaCl2 (aq) + CO2 (g) + H2O (l) f) Fe (s) + S (s) > _____ (s) 5 Rocks and building 1 The diagram shows a molecule of ammonia, NH3. H—N—H | H Match the words A, B, C and D with spaces 1 to 4 in the sentences. A bonds ……………….. B C D electrons ……………….. elements ……………….. symbols ……………….. Ammonia is a compound made from two ……… 1……… . The atoms in the molecule are represented by ……… ……… . The atoms in ammonia are held together by chemical ……… 3………. . Each atom has a nucleus surrounded by ……… 4………. . 2 The diagram shows stages in making cement and concrete. (4) Match statements A, B, C and D with the numbers 1 to 4 to describe what happens in this process. A B C D 3 cement mixed with sand and crushed rock ………. concrete produced ………. limestone heated in a kiln with clay ………. water added to mixture ………. (4) (a) Slaked lime is made by reacting quicklime with: A B C D carbon dioxide oxygen sulfuric acid water (1) b) The chemical name for slaked lime is: A B C D calcium chloride calcium hydroxide calcium oxide calcium sulfate (1) (c) Slaked lime can be used to make: A B C D bricks clay mortar quicklime (1) (d) Lime water goes cloudy when reacted with carbon dioxide. Which substance is produced? A B C D 4 calcium carbonate calcium chloride calcium oxide calcium sulphate (1) Glass is used in almost all buildings. (a) Suggest two properties of glass that make it useful in buildings. ………………………………………………………………………………………………………….. …………………………………………………………………………………………………………. (2) (b) Suggest and explain one disadvantage of using glass in buildings. ………………………………………………………………………………………………………….. ………………………………………………………………………………………………………….. (2) 5 One of the largest limestone quarries in the United Kingdom is near the town of Buxton. It is in the Peak District National Park, an area popular with tourists.

Suggest three social or environmental issues involved in quarrying limestone in the Peak District. ………………………………………………………………………………………………………………… ………………………………………………………………………………………………………………… ………………………………………………………………………………………………………………… (3) 6 Mortars used in most modern buildings are made using cement. A student tested the strength of a ready-mixed mortar.

He did this by dropping a mass onto a small mortar beam from increasing heights until the beam broke in half. He tested 4 beams made from the mortar. His results were 20 cm, 50 cm, 65 cm and 15 cm. (a) What was the range of the student’s results? ………………………………………………………………………………………………………….. ………………………………………………………………………………………………………….. (2) (b) Work out the mean of his results. ………………………………………………………………….. …………………………………….. (1) (c) Comment on the precision of his results. ………………………………………………………………………………………………………….. (1) (d) (i) Besides cement, what was the other solid in the ready-mixed mortar? …………………………………………………………………………………………………….. (1) (ii) What other solid is needed to make concrete instead of mortar? …………………………………………………………………………………………………….. 1) Rocks and Building past paper questions 1. Magnesium chloride is a useful salt. The flow diagram shows how it can be made. limestone calcium hydroxide seawater magnesium hydroxide acid magnesium chloride (i) Describe how calcium hydroxide can be made from limestone. ……………………………………………………………………………………………………………………. ……………………………………………………………………………………………………………………. …………………………………………………………………………………………………………………… ……………………………………………………………………………………………………………………. (2) (ii) Write a word equation for the neutralisation of magnesium hydroxide with a suitable acid to form magnesium chloride. ……………………………………………………………………………………………………………………. (2) (Total 4 marks) 2. (a) A student did some experiments to study limestone.

In one experiment, a piece of limestone was heated very strongly as shown in the diagram. Piece of limestone Tin lid The limestone was converted into quicklime and carbon dioxide. heat Limestone (i) quicklime + carbon dioxide Complete the symbol equation for this reaction. heat CaCO3 ………………. + CO2 (1) (ii) Give the chemical name for quicklime. …………………………………………………………………………………………………………… (1) (b) A student did another experiment to measure the mass of quicklime formed when 2 grams of limestone was strongly heated.

The limestone was weighed before and after being heated, using a balance reading to the nearest gram. The results are shown in the table. Mass of limestone before heating in grams Mass of quicklime formed in grams (i) (ii) 2 1 What mass of carbon dioxide was produced? ……………………………………….. g (1) Suggest ways in which the student could improve the accuracy and reliability of the measurements. …………………………………………………………………………………………………………… ………………………………………………………………………………………………………….. …………………………………………………………………………………………………………… …………………………………………………………………………………………………………… …………………………………………………………………………………………………………… …………………………………………………………………………………………………………… 3) (Total 6 marks) 3. Limestone is a useful rock. (a) Limestone can be used to make several useful products. Draw rings around two useful products made from limestone. cement (b) diesel glass petrol plastic (2) A student did some experiments to study limestone. In one experiment, a piece of limestone was heated very strongly as shown in the diagram. Piece of limestone Tin lid (i) Suggest one safety precaution that the student should take when doing this experiment. …………………………………………………………………………………………………………… ………………………………………………………………………………………………………….. (1) (ii) When limestone is heated it forms two products; a white powder and a gas. Complete the word equation by choosing the correct product from the list. calcium carbide oxide calcium hydroxide calcium nitride calcium calcium carbonate ? heat > ………………………………….. …… + carbon ?? dioxide (limestone) (1) (c) The student did another experiment using 2. 00 grams of limestone. The limestone was weighed before and after being heated. The student then repeated this experiment.

A new sample of 2. 00 grams of limestone was used. The results are shown in the table. Experiment 1 Mass of limestone before heating in grams (g) Mass of limestone after heating in grams (g) Mass lost in grams (g) (i) 2. 00 1. 12 0. 88 Experiment 2 2. 00 1. 10 0. 90 Calculate the average mass lost for the two experiments. ………………………………………………………………………………………………….. ………. Average mass lost = ………………………………………. g (1) (ii) Explain why it was important for the student to repeat this experiment. ………………………………………………………………………………………………………….. …………………………………………………………………………………………………………… (1) (iii) Suggest why the mass lost was not the same for the two experiments. …………………………………………………………………………………………………………… …………………………………………………………………………………………………………… (1) (iv)

Explain why a balance which measures to the nearest 0. 1 g would not be suitable for this experiment. …………………………………………………………………………………………………………… …………………………………………………………………………………………………………… (1) (v) Suggest what mass of carbon dioxide would be produced when 2. 00 g of limestone is heated. Mass of carbon dioxide produced = …………………… g (1) (d) The drawing shows a limestone quarry. (i) Suggest two ways in which the limestone quarry may harm the environment. ………………………………………………………………………………………………………… …………………………………………………………………………………………………………… …………………………………………………………………………………………………………… 2 ………………………………………………………………………………………………………… …………………………………………………………………………………………………………… 2) (ii) Suggest two ways in which the limestone quarry is of benefit to people. 1 ………………………………………………………………………………………………………… …………………………………………………………………………………………………………… 2 ………………………………………………………………………………………………………… …………………………………………………………………………………………………………… (2) (Total 13 marks) 4.

Limestone is an important raw material. (a) Limestone has many uses. Choose from the list two important materials made from limestone. cement poly(ethene) diesel oil sodium hydroxide glass sulphuric acid 1. ……………………………………………………………………………………………………………….. 2. ……………………………………………………………………………………………………………….. (2) (b) The diagram shows a lime kiln. The limestone is heated by the burning coal. Limestone and coal Waste gases Stream of air Quicklime (i)

Suggest why hot air is blown into the lime kiln. ………………………………………………………………………………………………………….. ………………………………………………………………………………………………………….. (1) (ii) Give two reactions which produce carbon dioxide in the lime kiln. Reaction 1 ………………………………………………………………………………………….. …………………………………………………………………………………………………………..

Reaction 2 ………………………………………………………………………………………….. ………………………………………………………………………………………………………….. (2) (c) (i) Quicklime (calcium oxide) can be converted to slaked lime (calcium hydroxide) by adding water. Write a word equation to represent this reaction. ………………………………. + ……………………………….. > ……………………………… (1) (ii) Why do farmers sometimes add slaked lime to acidic soil? …………………………………………………………………………………………………………. ………………………………………………………………………………………………………….. (1) (Total 7 marks) . An old lime kiln made in the ground is shown. Stones Coal Calcium carbonate Soil Soil Fire (a) The thermal decomposition of calcium carbonate makes a white solid and carbon dioxide. (i) Name a naturally occurring form of calcium carbonate. …………………………………………………………………………………………………………… ………………………………………………………………………………………………………….. (1) (ii) What does thermal decomposition mean? …………………………………………………………………………………………………………… …………………………………………………………………………………………………………… (2) (iii) Suggest and explain the purpose of the coal. …………………………………………………………………………………………………………… ………………………………………………………………………………………………………….. …………………………………………………………………………………………………………… (2) (iv) Write a word equation for the thermal decomposition of calcium carbonate. …………………………….. > …………………………….. + ……………………………… (2) (b) The diagrams show what happens when drops of cold water are added to the white solid formed by heating calcium carbonate.

Water White solid (ii) What type of chemical reaction takes place? Cracks appear …………………………………………………………………………………………………………… (1) (ii) Give the chemical name of the solid formed. Give a use of this solid. Name …………………………………………………………………………………………………. Use ……………………………………………………………………………………………………. (2) (Total 10 marks) Summary questions metals

Complete questions 1–5, and then do the ‘traffic lights’ self-assessment at the end. 6 Mark the following statements about crude oil and its fractions as true or false. i) j) l) Metals are found in rocks called ores. Reactive metals are often found in their native state. Carbon is often used to reduce metal oxides to the metal. true/false true/false true/false true/false true/false true/false true/false true/false true/false k) Reduction is the gain of oxygen by a metal. m) Copper can be obtained from its ores by smelting. n) Iron is produced in a blast furnace. o) In a blast furnace, limestone is added to reduce iron oxide. ) In a blast furnace, the iron oxide is reduced by carbon. q) The commonest ore of iron is called galena. 7 Fill in the gaps in the following paragraphs. Alloys are _____________ of metals. Steel is an alloy of _________. It is made up of this metal plus a small amount of _____________. Other _____________ can be added to steel to give it different ______________. For example chromium can be added to make ________________ steel. This type of steel is important because it does not _________. Brass is an alloy of _____________ and zinc. The ______________ is made harder by the addition of the zinc.

In brass the _______________ copper atoms cannot slide across each other so easily because the larger _______ atoms get in the way. The properties of alloys and steels determine their uses. For example, ________________ steel is used for cutlery. Brass is used for ___________ instruments because it looks good and does not corrode. 8 Cross out the wrong alternatives in the following paragraph. Aluminium is a shiny grey/orange metal. It is heavy/light and a bad/good electrical conductor. Therefore it is used for underground/overhead electrical cables. Other metals can be added to aluminium to make aluminium ores/alloys.

Even though aluminium is quite reactive/unreactive it does not corrode and this decreases/increases its usefulness. Aluminium should be recycled because it needs lots of electrical/kinetic energy to extract it. Also, aluminium ore or bauxite/haematite is running out. Titanium is a useful metal because it has a high conductivity/strength to weight/volume ratio. This means it is very strong and light/heavy and therefore, like aluminium, it can be used in the fishing/aerospace industry. It also does not corrode and is used medically to make replacement hips/eyes for people. Cross out the wrong alternatives in the following paragraph. There are several different ways of extracting metals. In ancient times the most reactive/unreactive metals like copper were extracted first. The method used here was either smelting/melting or oxidation/reduction. Reduction is the addition/removal of oxygen from the metal oxide. When we discovered electricity the more reactive/unreactive metals were then extracted using electrolysis/smelting. Another method that can be used is displacement of a less reactive metal by a more/less reactive one.

For example, magnesium will displace copper from magnesium/copper sulfate. Phytomining is a very recent method of extraction. This involves the selective uptake/emission of a metal by plants/animals. The plant/animal is then harvested along with the metal. 10 Fill in the gaps in the following paragraph. The transition metals are found in the ____________ of the periodic table. They form _______________ compounds. Their properties are typical of metals but they are often ____________ than non-transition metals. For example, iron can be used for __________ covers because it is heavy and will stay in place.

They are d____________ and therefore easy to draw into wires and m_____________ so they can be shaped easily. Traffic light self-assessment For each of the following topics, assess whether you: Red = Do not understand. Amber = Are not sure. Green = Understand. 1 Know the names of some metals found native and some found in metal ores. Red/amber/green 2 3 4 5 6 7 8 9 Know how to extract metals by smelting and reduction of their oxides. Red/amber/green Explain and understand the uses of steels. Explain that alloys are more useful than pure metals. Know about smart alloys and their uses.

Know the properties of transition metals. Know the methods for extracting copper. copper. Red/amber/green Red/amber/green Red/amber/green Red/amber/green Red/amber/green Red/amber/green Red/amber/green Compare the environmental impacts of the different methods of extracting Understand the uses and properties of aluminium and titanium. Rocks and metals 1 This question is about the uses of these metals: A C aluminium gold B D copper iron Which of these metals is used: (a) as the main metal in alloys to build aircraft? ……………….. (b) in alloys to make jewellery? ……………….. c) to make all steels? ……………….. (d) to make water pipes and electrical wiring? ……………….. 2 Choose a metal from the list A to D to match each description. A C aluminium gold B D chromium titanium (4) (a) A metal that is strong at high temperatures and resists corrosion. ………………………………………………………………………………………………………….. (b) An unreactive metal found native in the Earth. ………………………………………………………………………………………………………….. c) This metal has a low density and is extracted by electrolysis. ………………………………………………………………………………………………………….. (d) This metal is mixed with iron to make high alloy steels. ………………………………………………………………….. ……………………………………… (4) 3 Use words from the list A to D to complete the word equations. A C copper sodium B D iron water (a) copper oxide + sulfuric acid > copper sulfate + ……………….. (b) copper sulfate + iron > ……………….. iron sulfate (c) iron oxide + carbon > ……………….. + carbon dioxide (d) titanium chloride + ……………….. > titanium + sodium chloride 4 (4) A student tested the flexibility of four different alloy rods. She suspended a mass from the end of the rods which were fixed at the other end to the edge of a bench. She measured how far each rod bent. Which words describe the ‘distance the rod bent’? A B C D a categoric, independent variable. a continuous, independent variable. a categoric, dependent variable. a continuous, dependent variable. (1) 5 Name the types of substance described in each part of this question. a) These elements are hard, tough and strong, conduct heat and electricity well and are found in the middle of the periodic table. ………………………………………………………………………………………………………….. (b) These rocks contain enough metal to make it worth extracting. ………………………………………………………………………………………………………….. (c) This is a metal that contains other elements to give it specific properties. ………………………………………………………………………………………………………….. d) These materials are smart because they can return to their original shape when heated and are used by surgeons to hold broken bones while healing. ………………………………………………………………………………………………………….. (4) 6 Iron is extracted from iron oxide by removing oxygen. (a) What name is given to a reaction in which oxygen is removed from a compound? ………………………………………………………………………………………………………….. (1) (b) Name an element that could be used to remove oxygen from iron oxide. …………………………………………………………………………………………………………. (1) (c) Write a word equation for the reaction that would take place in (b). ………………………………………………………………………………………………………….. ………………………………………………………………………………………………………….. (2) 7 Titanium is used to make replacement hip joints. One reason why titanium can be used in this way is that it resists corrosion. a) How is titanium protected from corrosion? ………………………………………………………………………………………………………….. (1) (b) Suggest two other properties of titanium that make it suitable for this use. ………………………………………………………………………………………………………….. ………………………………………………………………………………………………………….. (2) 8 Most of the world’s steel is now made in Asia.

Suggest two reasons why it costs less to make steel in Asia than in Europe. ………………………………………………………………………………………………………….. ………………………………………………………………….. ……………………………………… (2) 9 New methods using bacteria, fungi and plants are being developed to extract copper. Suggest three reasons why these new methods have been developed. ………………………………………………………………………………………………………….. …………………………………………………………………………………………………………. ………………………………………………………………………………………………………….. (3) Metals past paper questions 1. A student was trying to extract the metals from lead oxide and aluminium oxide. She heated each oxide with carbon in a fume cupboard as shown below. lumps of charcoal (carbon) mixture of powdered carbon and the metal oxide very strong heat She was able to extract lead from lead oxide but not aluminium from aluminium oxide. i) Explain the results of these experiments. ……………………………………………………………………………………………………………………. ……………………………………………………………………………………………………………………. ……………………………………………………………………………………………………………………. ……………………………………………………………………………………………………………………. …………………………………………………………………………………………………………………… (ii) Complete this word equation for the reaction between lead oxide and carbon. lead oxide + carbon > ……………………………… + ………………………………… 2. Cassiterite is an ore of the metal tin. (a) What is an ore? …………………………………………………………………………………………………………………… ………………………………………………………………….. ……………………………………………… (2) (Total 5 marks) (b) Some metals are obtained by removing oxygen from the metal oxide. What name do we give to this chemical reaction? …………………………………………………………………………………………………………………… (1) (c) Name one metal which must be extracted from its melted ore by electrolysis rather than by using carbon. …………………………………………………………………………………………………………………… (1) (Total 4 marks) 3. The word box contains the names of some metals. luminium (i) copper iron manganese zinc The drawing shows the view from a window. Choose from the names of metals in the box to complete the three spaces. (3) (ii) What is the name of the metal in the word box which has the chemical symbol Fe? ……………………………………………………………………………………………………………………. (1) (iii) What is the name of one metal in the word box which often has coloured compounds? ……………………………………………………………………………………………………………………. 1) (Total 5 marks) 4. One step in the manufacture of lead is the reduction of lead oxide with carbon. Lead and carbon dioxide are the products of this reaction. (a) Write a word equation for this reaction. ……………………………………………………………………………………………………………………. (1) (b) What is meant by “reduction”? ……………………………………………………………………………………………………………………. (1) (Total 2 marks) 5. Alloys have many important uses. (a) State the meaning of the term alloy. …………………………………………………………………………………………………………………… ……………………………………………………………………………………………………………………. (1) (b) This wedding ring is made from 18 carat gold. This is an alloy made from gold and silver. The wedding ring has to last many years when worn every day. Suggest and explain why the ring is made from an alloy rather than pure gold. ……………………………………………………………………………………………………………………. …………………………………………………………………………………………………………………… (2) (c) The metal frame of these glasses is made from a smart alloy. This alloy is made from titanium and nickel. Give one advantage of making the frame from a smart alloy, instead of an ordinary metal. ……………………………………………………………………………………………………………………. ……………………………………………………………………………………………………………………. (1) (Total 4 marks) . The table gives information about some metals. Name of the metal Aluminium Platinum Iron Gold (a) Cost of one tonne of the metal in December 2003 (? ) 883 16720000 216 8236800 Percentage of the metal in the crust of the earth (%) 8. 2 0. 0000001 4. 1 0. 0000001 Use information in the table to suggest why gold and platinum are very expensive metals. ……………………………………………………………………………………………………………………. ……………………………………………………………………………………………………………………. 1) (b) Aluminium and iron are made by reduction of their ores. (i) Name the element that is removed from the ores when they are reduced. …………………………………………………………………………………………………………… (1) (ii) Use the reactivity series on the Data Sheet to suggest a metal that would reduce aluminium ore. …………………………………………………………………………………………………………… (1) (c) Aluminium is made by the reduction of molten aluminium ore, using a very large amount of electricity. i) How is iron ore reduced in a blast furnace to make iron? …………………………………………………………………………………………………………… …………………………………………………………………………………………………………… …………………………………………………………………………………………………………… …………………………………………………………………………………………………………… (2) (ii) Suggest why aluminium is more expensive than iron. ………………………………………………………………………………………………………….. …………………………………………………………………………………………………………… (1) (Total 6 marks) Summary questions Crude Oil Complete questions 1–4 and then do the ‘traffic lights’ self-assessment at the end. 10 Mark the following statements about crude oil and its fractions as true or false. r) t) Crude oil is a mixture of different compounds. Crude oil can be split up into fractions using filtration. oiling points. v) The fractions contain hydrocarbons called alkanes. x) The general formula of the alkanes is CnH2n+2. y) The fuels from crude oil are non-renewable. z) The alkane with ten carbons has the formula C10H24. aa) The process used to separate the fractions is called fractional distillation. with the place where they leave the column. true/false 11 Given below is a simple diagram of a fractionating column. Match the fractions true/false true/false true/false true/false true/false true/false true/false true/false s) Crude oil is a pure substance. ) The fractions are easily separated because they have different w) Hydrocarbons contain the elements hydrogen, carbon and oxygen. true/false 12 Fill in the gaps in the following paragraphs. When hydrocarbon fuels burn in air they react with ______________ gas. If there is sufficient air present then ________________ combustion takes place. __________ is formed along with carbon dioxide gas. If there is not enough air for ______________ combustion then incomplete combustion takes place. If this happens then the poisonous gas, _________________ __________________ is formed.

This gas stops _____________ getting to the brain and the person can become asphyxiated. If there is very little air present then solid ______________ can form and this forms as a ____________ solid deposit. If the hydrocarbon fuel contains sulfur then the gas ________________ dioxide can form. This dissolves in water in rain clouds to form _________ rain. This can cause damage to ___________________, harm trees and affect the health of _______________. 13 Cross out the wrong alternatives in the gaps in the following paragraphs.

Fossil fuels contain hydrocarbons/carbohydrates and when these burn pollutants are produced. Carbon dioxide is a greenhouse/white house gas and reduces the amount of heat/sound energy lost by radiation. This causes global cooling/warming. This could have several consequences, some of which might be harmful. For example, the ice-caps might freeze/melt and this could raise/lower water levels in the oceans and cause flooding. When diesel fuels burn they give off particulates/participles and these are tiny gas/solid particles thought to cut down light from the Moon/Sun.

This in turn causes global illumination/dimming. Other pollutants formed by the burning of fossil fuels are sulfur dioxide/trioxide and oxides of nitrogen/argon. These are thought to cause asthma/blindness in humans. Traffic light self-assessment For each of the following topics assess whether you: Red = Do not understand Amber = Are not sure Green = Understand 14 Crude oil is a fossil fuel. 15 Crude oil is a non-renewable source of fuel. 16 Crude oil is a mixture of hydrocarbons. 17 Crude oil is separated using fractional distillation. fractionating column. 20 Alkanes have the general formula, CnH2n+2.

Red/amber/green Red/amber/green Red/amber/green Red/amber/green Red/amber/green Red/amber/green Red/amber/green 18 The fractions with low boiling points come off near the top of the 19 Hydrocarbons are compounds of hydrogen and carbon only. Red/amber/green 21 Crude oil from different areas of the world have different thicknesses. 22 Hydrocarbons burn in air to form carbon dioxide and water. particulates which are both poisonous. nitrogen which both form acid rain. Red/amber/green Red/amber/green Red/amber/green Red/amber/green 26 Particulates are thought to cause global dimming. 7 Gasohol and biodiesel are cleaner renewable fuels. Red/amber/green Red/amber/green 23 Incomplete combustion of hydrocarbons gives carbon monoxide and 24 When fossil fuels are burned in air they give off sulfur dioxide and oxides of 25 Carbon dioxide is a greenhouse gas and is a cause of global warming. Crude oil 1 The following compounds are found in crude oil: A B C D C3H8 C8H18 C12H26 C16H34 Which of these compounds: (a) has the highest boiling point? ……………….. (b) catches fire most easily? ……………….. (c) is collected at the top of the fractionating column when crude oil is distilled? ………………. (d) is the thickest liquid? ……………….. 2 Crude oil is a mixture of many different hydrocarbons. (4) Match the words A, B, C and D with spaces 1 to 4 in the sentences. A B C D alkanes ……………….. compounds ……………….. fractions ……………….. molecules ……………….. (a) Crude oil is separated by distillation into ……… 1……… containing hydrocarbons with similar boiling points. (b) Hydrocarbons with the smallest ……… 2……… have the lowest boiling points. (c) Hydrocarbons are ……… 3……… f hydrogen and carbon only. (d) Crude oil contains mostly saturated hydrocarbons called ……… 4……… . 3 The table shows the number of carbon atoms in the molecules of four fuels obtained from crude oil. Fuel petroleum gases petrol kerosene diesel oil Number of carbon atoms in molecules 2–4 4–10 10–15 14–19 (4) (a) The fuel with the highest boiling point is … A B C D petroleum gases petrol kerosene diesel oil (1) (b) Petrol … A B C D has a higher boiling point than diesel oil. is a thinner liquid than diesel oil. ignites less easily than kerosene. has larger molecules than kerosene. (1) c) The molecule C4H10 could be in … A B C D petrol only. petrol and kerosene. petrol and petroleum gases. petroleum gases only. (1) (d) Which one of the following is a saturated hydrocarbon that could be in diesel oil? A B C D 4 C12H26 C16H32 C17H36 C18H38O (1) Pentane, C5H12, is a hydrocarbon fuel. It burns completely in plenty of air. (a) Name the gas in the air that pentane reacts with when it burns. ………………………………………………………………………………………………………….. (1) (b) Write a word equation for the combustion of pentane in plenty of air. …………………………………………………………………………………………………………. ………………………………………………………………………………………………………….. (2) (c) Write a balanced symbol equation for this reaction. ………………………………………………………………………………………………………….. ………………………………………………………………………………………………………….. (2) (d) When the air supply is limited a poisonous gas is produced.

Name this gas. ………………………………………………………………………………………………………….. (1) (e) Write a balanced symbol equation for the combustion of pentane in a limited supply of air. ………………………………………………………………………………………………………….. ………………………………………………………………………………………………………….. (2) 5 (a) Suggest two fuels that could be used in place of fossil fuels. Give one advantage and one disadvantage for each of the fuels you have named. …………………………………………………………………………………………………………. ………………………………………………………………………………………………………….. ………………………………………………………………………………………………………….. ………………………………………………………………………………………………………….. ………………………………………………………………………………………………………….. …………………………………………………………………………………………………………. (6) 6 Oil companies promote the use of low sulfur fuels. (a) Explain why it is better to use low sulfur fuels. ………………………………………………………………………………………………………….. ………………………………………………………………………………………………………….. ………………………………………………………………………………………………………….. 3) (b) Suggest one other reason why oil companies advertise that their fuels are low in sulfur. ………………………………………………………………………………………………………….. (1) 7 Crude oil is separated by fractional distillation. In oil refineries this is done in tall towers called fractionating columns. Give the main steps in this process and explain how the different fractions are separated in a fractionating column. ………………………………………………………………………………………………………………… ……………………………………………………………………………………………………………….. ………………………………………………………………………………………………………………… ………………………………………………………………………………………………………………… (4) Crude oil past paper questions 1. Methane CH4 contains the elements carbon and hydrogen only. A student wanted to find out which new substances are produced when methane is burned. The student set up the apparatus shown below. uction pump methane gas ice + water liquid collects here limewater turns milky (a) Which gas in the air reacts with methane when it burns? ……………………………………………………………………………………………………………………. (1) (b) Name the liquid collected. ……………………………………………………………………………………………………………………. (1) (c) Name the gas which turns limewater milky. ……………………………………………………………………………………………………………………. 1) (d) When methane burns an exothermic reaction takes place. What is meant by an exothermic reaction? ……………………………………………………………………………………………………………………. ……………………………………………………………………………………………………………………. (2) (Total 5 marks) 2. The equation below shows the cracking of a hydrocarbon compound into two different compounds, A and B. H H C H H C H H C H H C H H C H H C H H H C H H C + H H H C H H C H H C H H C H H Compound A Compound B (a)

State two differences between the structures of compounds A and B. ……………………………………………………………………………………………………………………. ……………………………………………………………………………………………………………………. ……………………………………………………………………………………………………………………. ……………………………………………………………………………………………………………………. 2) (b) Why is compound A useful in industry? ……………………………………………………………………………………………………………………. ……………………………………………………………………………………………………………………. (1) (Total 3 marks) 3. Crude oil is a mixture of long-chain hydrocarbons. It is cracked to produce a mixture of smaller alkanes and alkenes. Among the gases formed are ethane and ethene. (a) Write the structural formula for: (i) ethane (1) (ii) ethene (1) (iii)

Give an example of one chemical reaction which both ethane and ethene undergo. …………………………………………………………………………………………………………… (1) (iv) Describe how to distinguish between ethane and ethene. Include a description of the practical method you would use and what you would expect to observe. …………………………………………………………………………………………………………… …………………………………………………………………………………………………………… ………………………………………………………………………………………………………….. …………………………………………………………………………………………………………… …………………………………………………………………………………………………………… …………………………………………………………………………………………………………… (3) (b) Ethene may be polymerised to form a polymer. Give the name of the polymer and a use for it.

Name ……………………………………….. Use ………………………………………………….. (1) (Total 7 marks) 4. Crude oil and natural gas are mixtures of hydrocarbons. They are obtained from wells drilled into rocks where they are trapped. (a) (i) What is the name of the process used to separate the different hydrocarbons in crude oil? …………………………………………………………………………………………………………… (1) (ii) Methane is one of the gases obtained when crude oil is separated. Give the name of another hydrocarbon gas obtained from this process. ………………………………………………………………………………………………………….. (1) (b) A fuel used in gas cookers is natural gas. It is mainly methane, CH4. (i) Complete the word equation for the complete combustion of methane. methane + oxygen > ……………………………… + ………………………………………. (ii) What different gas is produced by the incomplete combustion of methane? ………………………………………………………………………………………………………….

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