What is a metal ore?

What is a metal ore? An ore is any kind of rock or mineral from which a metal can be profitably extracted. Metals are rarely found uncombined (as elements) in nature. They are nearly always present in the forms of compounds, often where the metal is chemically joined with oxygen. Only the most unreactive metals, like silver and gold will be found pure. The most common metals are oxides and sulphides. Ores are rocks from which we extract metals. Metals are found naturally in rocks called ores. They are in compounds, chemically bonded to other elements. However, the unreactive metals are at the bottom of the reactivity series can be found as the elements themselves. We say they are found native. We can find copper, silver, gold and platinum as the metals in nature. What factors do companies consider when deciding whether to extract a metal from its ore? There are many different factors that the companies will look for, a few of them are: - How much will it cost? - How to extract the metal? - How much the metal will be worth etc. What are the three methods of metal extraction? Given that most metals are only found locked up in their ores, but how do you go about getting them out? For a few metals, such as mercury, heat will do the trick. But for most ores the temperatures needed are far too high to make this a practical possibility. Another approach is needed. There are

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An investigation to see how voltage affects The electrolysis in a copper Sulphate solution using copper electrodes.

An investigation to see how voltage affects The electrolysis in a copper Sulphate solution using copper electrodes. Aim To find out how the voltage affected the electrolysis in a copper sulphate solution by weighing the amount of copper that was on the anode and the cathode and then comparing the difference from before the electrolysis. Theory Electrolysis is the process of decomposing the compounds by electrical energy and an element is produced at each electrode. In this case I have chosen copper sulphate solution to electrolyse. In the experiment when the solution is being electrolysed it starts to decompose and at cathode there is copper formed and oxygen at the anode. This is caused by electricity from the power supply, which has caused a chemical change. The reaction, which occurs at the cathode, is: Cu2+ (aq) +2e- › Cu (s) The reaction, which occurs at the anode, is: Cu (s) › Cu2+ (aq) + 2e- Variables The possible independent variables that could have been tested in this test are the following; the amount of copper sulphate in the beaker, the current, the voltage, the size of anode and cathode, the duration of time given for it to electrolyse and the distance between the anode and the cathode whilst inside the electrolyte In this test we have decided to set the voltage as our independent variable. We will then see how much copper is deposited after 3

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How are products from oil obtained and used?

How are products from oil obtained and used? Crude oil is a vital substance used frequently in our everyday lives. However we are all aware that oil is being used faster than it can be produced and that there are only scarce amounts left. The question is how can we make these products last as long as possible and what are the alternatives? Crude oil is a fossil fuel, made naturally from decaying plants and animals living in ancient seas millions of years ago. It is usually found under the ground and under the sea in certain parts of the world such as the Middle East and Texas, in the USA. Although crude oil is very important substance, the oil itself has no direct use, so has to be refined. The first step in the refinery of crude oil is fractional distillation. Fractional distillation is used to separate fractions such as gasoline, bitumen, kerosene, petroleum, fuel oil, etc from crude oil. During fractional distillation the crude oil is split into a variety of fractions, during the process each fraction of the crude oil will evaporate and can therefore be collected by condensing it. This means that if you know the certain boiling points of each fraction you can separate the certain substance you need. The process begins in the oil refinery. In the oil refinery the crude oil is heated to turn the oil in to a vapour; it is then fed into the bottom of the fractionating

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Is Aluminium a Suitable Metal for Manufacturing Bicycles?

Is Aluminium a Suitable Metal for Manufacturing Bicyces? Extraction Process for Aluminium The ore of aluminium is Bauxite and it contains 52.9% aluminium and 47.1% oxygen. The extraction of aluminium takes three main stages: * The mining of bauxite * Refining of the ore to produce aluminium oxide * Electrolysis of aluminium oxide to produce aluminium Mining Bauxite is mined by removing the top layers of soil and then removing the ore from the area by use of explosives to break it into moveable pieces. The bauxite is then crushed on site, sometimes washed to remove soil and clay and then dried in a kiln or it may just be dried. It is then ready to be transported by railway or ships to refineries. Refining Bauxite is made of aluminium oxide-2-water (Al2O3.2H2O) and silicon (IV) oxide (SiO2) and iron (III) oxide (Fe2O3). The bauxite is refined to extract pure aluminium oxide: * The bauxite is ground * Then heated with concentrated NaOH (aq) * This forms a solution of sodium aluminate and sodium silicate, plus a residue of iron (III) oxide, which is removed. * CO2(g) is blown in and the sodium silicate remains in solution, but a precipitate if aluminium hydroxide is formed. * The mixture is then filtered, washed and heated to leave anhydrous aluminium oxide (alumina). * Al2O3 is left. Electrolysis This is how the aluminium and oxygen is separated, through

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How the concentration of brine affects the conduction of electricity.

Electrolysis Investigation Aim: How the concentration of brine affects the conduction of electricity Background Information: Electrolysis: Metals that are more reactive than carbon are extracted by electrolysis. Electrolysis is the break down of a substance by electricity. Electrolysis only occurs in when an ionic substance is molten or is in solution. A substance that can be electrolysed is called an electrolyte. Electrolytes are made up of ions. Electrolytes need to be molten or in solution, so that the ions present are free to move. Ionic compounds have high melting points, so it is often easier to electrolyse the solution of the ionic compound. When the electrodes are connected to a source of direct current one, called the cathode, becomes negatively (-) charged while the other, called the anode, becomes positively (+) charged. The positive ions in the electrolyte will move toward the cathode and the negatively charged ions toward the anode. This migration of ions through the electrolyte constitutes the electric current in that part of the circuit. The migration of electrons into the anode, through the wiring and an electric generator, and then back to the cathode constitutes the current in the external circuit. Concentration: The concentration of a mixture also effects the rate of reaction. An increase in concentration means there are more particles. More

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An investigation into the factors which affect the currentflowing during electrolysis

An investigation into the factors which affect the current flowing during electrolysis Introduction Electric current is the flow of electrons. Sodium chloride in solution is able to conduct electricity because when dissolved sodium ions and chloride ions are produced. The chloride ions that are negatively charged due to their extra electron are attracted to the anode where they give up that extra electron and bond with other molecules to form the chlorine gas, Cl2. The extra electron then flows through the circuit to the cathode. H+ ions in the solution are attracted to the negative charge of the cathode and there they gain the extra electrons that originally belonged to the Cl- ions. Hydrogen gas is then formed and the circuit is complete. 2e + 2H+ --> H2 2Cl- - 2e --> Cl2 Variables Concentration of NaCl- The bigger the concentration the more ions will be in the solution. This will mean that more ions will get to the electrodes, which means more electrons will get into the wire. This will greater the current. Temperature- the ions will go quicker to the electrodes as the water will vibrate quicker when hotter. This will increase the current. Voltage- The current would be decreased because by ohm's law v=ir Surface area of the electrodes- if the surface area on the electrode increases there will be more space for the ions to go to and therefore the current will

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Effect of increasing charge on Mass of Copper Deposited.

Chemistry Coursework Effect of increasing charge on Mass of Copper Deposited Diagram Method * I will fist weigh the cathode * I will then set up the apparatus as shown in the diagram * Then switch the power pack on * I will wait 10 minutes and then weigh the cathode, I will do this for 50 minutes every 10 minutes My Independent Variable is the Charge My Dependent Variable is the Mass of the cathode The controlled variables are the concentration of Copper sulphate and the temperature Prediction: I can predict that there will be a positive coloration between the increase of charge and the amount of copper produced at the cathode. Scientific Explanation: Current is the flow of electrons in a circuit - in the case of electrolysis the flow is towards the cathode and away from the anode. Within the solution, the current flows because of the presence of negative and positive ions. Copper sulphate is an ionic salt, which contains no free electrons. However, it does contain ions (which are charged particles) fixed in a crystalline structure. When copper sulphate is dissolved, the copper sulphate solution becomes an electrolyte because the ions become free to move and they can conduct electricity. At the cathode, the copper ions, being more reactive than the hydrogen ions are deposited whilst the hydrogen ions

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Controlled Assessment - Fertlilisers Research

Fertilisers Fertilisers are made from ammonia and are used in modern farming as they increase crop yield. The three main fertilisers made from ammonia include, ammonium nitrate, ammonium sulphate and urea. How are they manufactured? Fertilisers are made by the reaction of an acid and an alkali. The preparation of a fertiliser in a lab involves the following equipment: a measuring cylinder to measure the volume of a particular acid, a burette to add an alkali to the acid to try and make the solution neutral and a filter funnel to remove the solid crystals of fertiliser from the solution. The pH (power of hydrogen) value of the solution can be measured by taking samples while using universal indicator. In our examples; ammonia is reacted with nitric acid to make ammonium nitrate and ammonia is reacted with sulphuric acid to make ammonium sulphate. [2] NH3 + HNO3 › NH4NO3 Ammonia + Nitric Acid › Ammonium Nitrate NH3 + H2SO4 › (NH4)2SO4 Ammonia + Sulphuric Acid › Ammonium Sulphate When these fertilisers are manufactured in a factory the ammonia and the acid are pumped into a mixing vessel, where the solution is neutralised. The solution is then heated and the water evaporates off leaving the molten ammonium nitrate/sulphate which is sprayed into a cooling chamber. Air is blown into the bottom of the cooling chamber to cool the ammonium nitrate/sulphate. The

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the chemistry of iron

Write an essay on the chemistry of iron Introduction Iron has an electronic configuration of . It is a d-block element. Also, iron is a transition metal. It has all the properties of a transition metal, including variable oxidation states, complex formation, coloured ions and catalytic properties. General properties of iron Like other metals, iron has a shiny surface. It conducts heat and electricity well. Iron is very tough, so it is always used as building materials. Moreover, iron is cheap when compared with other metals; therefore, it is widely used in all kinds of manufacturing. Variable oxidation states Since the successive ionization enthalpies of transition metals only increases gradually and in particular, the energy difference between 3d and 4s shells is very small, transition metals have variable oxidation states. Iron has two major oxidation states: +2 and +3. Fe2+: Fe3+: As Fe3+ has a half-filled 3d subshell, Fe3+ has extra stability over Fe2+. This can be reflected from the particularly low third ionization enthalpy. Fe2+ can readily be oxidized to Fe3+. Coloured ions and complex formation Complex is formed when ligands form dative covalent bonds with the central atom/ion. Transition metal ions like Fe2+ and Fe3+ can form complexes with ligands readily because they have large charge/radius ratio and low lying vacant d-orbitals available for

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Extraction Of Iron

Extraction Of Iron Iron, perhaps the most important element to all civilization is also one of earth's most abundant. Like the majority of metal ores, iron ores are not pure compounds. Rather, most iron ore compounds are polluted with sand, rock and silica. The process of extracting iron involves a number of steps. The first step to concentrate the iron ore and remove its contents of silica. To further remove any existing impurities, a complex process takes place in a blast furnace. The charge is where materials are placed into the blast furnace. These materials are: Ore, Limestone and Coke. A burst of hot, oxygen enriched air is blown into the air-blast nozzle located at the near bottom of the furnace. What follows are a number of oxidation and reduction type reactions which ultimately produce the metallic iron. One of these reactions is the coke being burnt. The heat generated by this reaction increases the bottom of the furnace to a temperature near 19000° C. This reaction is represented in a chemical equation: C(s) + O2(g) (r) CO2(g) + heat The carbon dioxide generated rises halfway up the furnace, where it reacts with the hotter coke. This causes the carbon dioxide to reduce into carbon monoxide. This reaction absorbs some heat and lowers the temperature of the upper part of the furnace to roughly 1300° C. CO2(g) + C(s) + heat (r) 2CO(g) This

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