To find out how current affects the rate of electrolysis

Electrolysis experiment. Aim: To find out how current affects the rate of electrolysis. Pre-test: Pre-test Apparatus: . Power Pack 2. Stop watch 3. 3 wires 4. Amp meter 5. A piece of Card 6. stop watch 7. Top pan balance Pre-test Method: . Check to see if all the apparatus work by forming a small circuit with a bulb 2. Collect apparatus and set them out like the diagram below. Ensure that the positive wire leads to the anode and the negative leads to the cathode. 3. Measure out 50 ml of copper sulphate 4. In to a small class beaker 5. Weigh cathode on top pan balance 6. Slide anode and cathode in to piece of card and place in electrolyte 7. Turn on the power pack 8. Time until two minutes 9. Weigh cathode make sure you do not scrape off any copper 0. Repeat three times 1. Repeat for each current Pre-test Findings: By doing this pre-test I have learnt that: * The analog amp meter is very unreliable it * To be very accurate I need to use a multi meter * To be careful not to scrape of copper when measuring weight * Make sure that the anode and the cathode do not touch during the experiment * Make sure wires and power packs are working before you start * To change the electrolyte after each experiment * To use a stop watch instead of a clock as it is more accurate * To use a variable resistor to get the exact current you need Research: There are

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Suitability Test

Suitability Test Introduction My work is about a scenario where a building contractor that wishes to develop an area of land into new houses for families. The Environment Agency has been asked to check the land for contamination. My task is to decide which method of testing Ph values in soil is most suitable for an environmental scientist. The desirable characteristics should be: * Safe: So no one is harmed whilst using it. * Easy To Use: So its easier to carry out more than once * Accurate: So that the readings are reliable. * Light: So it is easy to carry around. * Portable: So that it is easy to transport around. * Durable: So it can last longer. * Small: So that it's easier to transport. * Cheap: So it saves money and is cost effective. * Energy Efficient: So it doesn't need a mains power supply. Evaluation RED= Poor ORANGE= Average GREEN= Good Cost Litmus U.I. Solution Soil Probe pH Probe About 3p £4.15 £6.95 £294.46 Accuracy Litmus U.I. Solution Soil Probe pH Probe Acid/Alkali 0.5 .0 0.01 Time for results Litmus U.I. Solution Soil Probe pH Probe 5 Minutes 5 Minutes Minute 5-10 Minutes Sensitivity Litmus U.I. Solution Soil Probe pH Probe Acid/Alkali -14 Full Range 4-7 Full Range - More Accurate Durability Litmus U.I. Solution Soil Probe pH Probe ***** *** **** **** Easy To Use Litmus U.I. Solution

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The Age of the Earth

The Age of the Earth In 1654 it was calculated that the earth had formed on October 23, 4004 BC. James Ussher made this discovery from the Bible. Nowadays the age of the earth is determined to be at least 4.5 billion years old. People all over the world now disagree with Ussher's theory because of religious reasons and most Christians still believe that the Earth was created 4004BC. Almost all of our evidence towards the Earth's age comes from the examination of rocks. People who analyse new discoveries of fossils and meteorites can possibly lead us to knowing the age since we can examine carbon and radiocarbon dating. Fossils in sedimentary rocks and the weathering of most ancient craters prove to us that some of the eldest bits rocks date back to about 4.5 billion years old. There is evidence to prove that the earth had formed approximately 1 billion years ago by radiometric age dating of particular rocks, such as lead in uranium-rich minerals which had showed us that it was in excess of being a billion years old. However the oldest bits of minerals to be discovered are small crystals of zircon that was found at Jack Hills of Western Australia. The dating of these minerals were approximately 4.404 billion years old. The earth must have been as old as any formation on it and information such as this can easily be considered as proof of the earth's existence meaning that

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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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Atmospheric pollutants in the lower atmosphere essay.

Atmospheric pollutants in the lower atmosphere The atmosphere becomes polluted by both natural processes and the activities of humans. Volcanoes can release toxic gases including sulfur dioxide. Lightning produces toxic nitrogen oxides and ozone. Let us examine some gases that pollute the lower atmosphere. Lower atmospheric pollutants often include particulates such as soot from forest fires and the exhaust from industry. Metal dusts and concrete dusts also are atmospheric pollutants, as are vapours from solvents used in industry and domestically. Carbon dioxide The concentration of carbon dioxide has shown a gradual increase during the twentieth century. The burning of fossil fuels such as coal and oil products has caused this gradual increase in carbon dioxide levels. This increase in carbon dioxide is one of the factors that scientists believe has added to global warming. This is sometimes referred to as the 'enhanced greenhouse effect'. Carbon dioxide absorbs infrared (IR) radiation that is re-radiated by the Earth's surface. This process is vital in ensuring that the Earth does not lose too much heat and become a cold, lifeless planet. Too much carbon dioxide, however, leads to higher heat retention with consequent changes to the abiotic and biotic environment. Carbon monoxide Carbon monoxide is a lower-atmospheric pollutant. Road traffic emissions account for up

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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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Aerosols in Atmosphere - Environmental and Economical Impact.

Eni Ballauri 9A Chemistry Aerosols in Atmosphere Environmental and Economical Impact We have heard that greenhouse gases, mainly carbon dioxide, are leading to global warming. But, another factor has been identified that affects Earth's atmosphere; aerosols. Aerosols are small particles or droplets in the atmosphere. Aerosol particles may be created by wind blowing over dusty regions, and also by the conversion into tiny particles of some of the gases emitted by plants and volcanoes. Some aerosols remain in air only a few days, so they don't have much time to travel away. But nevertheless, they affect our surrounding environment at the local and global levels. It is also recognised as a health problem, especially in regard to respiratory illness. Atmospheric aerosols influence climate. They reflect the sunlight back to space, in a way that provides the gradual cooling of planet Earth. A professor in CU-Boulder's Laboratory for Atmospheric and Space Physics, Toon, who has studied similar modification of clouds over the ocean and their effects, said that aerosol cloud may even cancel out greenhouse warming. During winter, in polar regions, polar stratospheric clouds form. This provides sites for chemical reactions to take place. These reactions can lead reaction of reactive chlorine, which destroys the ozone. Contrary, because of loosing the ozone layer, Earth will lose

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An Investigation Into What Affects How Much Copper Is Deposited On A Pure Copper Cathode.

An Investigation Into What Affects How Much Copper Is Deposited On A Pure Copper Cathode. Plan Aim The aim of this investigation is to find out what effects the amount of copper deposited on a pure copper cathode. We already know that by passing an electric current through a copper sulphate solution the atoms at the anode dissolve while at the cathode positive ions are gathering and collect up. Variables Variables are what we can change in the experiment here are some of them: * We can change the amount of current passed through the electrodes. * We can change the strength of the solution by adding and reducing the amount. * We can also vary how long the experiment is left while an electric current is passed through the electrodes. We choose to change the amount of current passed through the electrodes using a variable resistor. I choose this because it is simple and gives off good and clear results. Predictions A simple prediction would be to say that the mass of copper deposited at the anode would decrease, and the mass of copper deposited at the cathode would increase. It is also possible to predict when using time as a variable, that the relationship between the time the current flows and the mass of copper deposited at the cathode will be proportional. I can then predict that if I double the time of the experiment, I will be doubling

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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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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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