Water clocks‚ along with sundials‚ are likely to be the oldest time-measuring instruments‚ with the only exceptions being the vertical gnomon and the day-counting tally stick.[1] Where and when they were first invented is not known‚ and given their great antiquity it may never be. The bowl-shaped outflow is the simplest form of a water clock and is known to have existed in Babylon and in Egypt around the 16th century BC. Other regions of the world‚ including India and China‚ also have early evidence
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A ‘clock’ is an instrument used to specify‚ record‚ and manage time. The word ‘clock’ comes from the French word “cloche” meaning bell‚ came into use when timekeepers were kept in bell towers in the Middle Ages. Historians do not who or when mankind “invented” a time-keeping device or a “clock”. Probably thousands of years ago when someone stuck a stick in the ground and saw a shadow of the sun move across the ground‚ known as the sundial. (Cummings‚ 1997-2012). After the Samarian culture
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This experiment was a Landolt Iodine clock reaction - Oxidation of Bisulphite by Iodate. It involved conducting three measured experiments. The first variable tested was concencentration. This was tested by conducting two experiments‚ each varying the concentration of either the NaHSO3 or KIO3. The varying of NaHSO3 involved using 0.1 Molar of KIO3 against decreasing concentrations of NaHSO3 (0.25 M‚ 0.125 M‚ 0.0625 M and 0.03125 M). When decreasing the concentration of KIO3‚ 0.25 M of NaHSO3 was
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CHM1022 Lab Report 1 Rate Law of an Iodine Clock Reaction Name: Sashini Naomi Wijesekera Student ID: 23877847 Lab Partner: Zahiya Imam Lab Session: Monday 9.00am Aim The aim of the experiment is to determine the factors that affect the rate of a reaction‚ by performing the iodine clock reaction and repeating it changing different initial conditions in order to measure and compare the rate of reaction for each experiment and experimentally determine
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Substance Hazard images Exposure Symptoms Prevention First aid Spillage/Disposal Storage PREVENT GENERATION OF MISTS! AVOID ALL CONTACT! IN ALL CASES CONSULT A DOCTOR! Hydrogen peroxide Hydrogen dioxide Dihydrogen dioxide H2O2 Molecular mass: 34.0 20% Vol and lower Corrosive to metals‚ category 1 Skin corrosion‚ categories 1A‚ 1B‚ 1C Serious eye damage‚ category 1 Oxidizing gases‚ category 1 Oxidizing liquids‚ categories 1‚2‚3 Inhalation Sore throat. Cough. Dizziness
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Using the Iodine clock method to find the order of a reaction Introduction When peroxodisulfate (VI) ions and iodide ions react together in solution they form sulfate (VI) ions and iodide. This reaction is shown below: S2O82-aq+ 2I-aq SO42-aq+ I2(aq) The reactants and the sulfate (VI) ions are colourless however the Iodine is a yellow/brown colour. This allows you to measure the progress of the reaction through the colour change when the iodine is produced. In order to determine the order of
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the form of a metal ion affect the rate of reaction in an iodide clock reaction with potassium peroxydisulphate ions? Background When peroxydisulfate ions (S2O82-) react with iodide ions (I-) in the presence of a starch indicator‚ they produce a dark blue solution. Reaction (1) S2O82- + 3I- I3- + 2 SO42- (peroxydisulfate ion) (iodide ion) (iodine ion) (sulfate ion) To determine the rate law for this reaction a series of changes in the concentration of
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perform an experiment known as the "iodine-clock" reaction‚ in which hydrogen peroxide reacts with iodide to form iodine‚ and the iodine subsequently reacts with thiosulfate ion until the thiosulfate has been consumed. At that point‚ the reaction solutions turn blue in the presence of starch. The experiment helps students understand the fundamentals of chemical kinetics --- the speeds at which reactions take place. 1. Activation Energy * Chemical reactions are thermodynamically "favorable" if
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Mechanism of Bromine Addition to Alkenes Understanding the chemical mechanism (order of bonds broken and made as well as intermediates formed) has a great value in chemical synthesis. The chemical mechanism of a reaction will influence the rate of the reaction‚ the stereochemistry of the product(s)‚ and the extent of possible undesired side reactions. Organic reaction mechanisms investigate the path towards a desired product and not just the destination of that product. In this reaction‚ we will examine
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1.0 Introduction According to (Baillie et al.‚ p. 307; Palmer‚ p. 19) “A clock is an instrument used to indicate‚ keep‚ and co-ordinate time. The word clock is derived ultimately (via Dutch‚ Northern French‚ and Medieval Latin) from the Celtic words clagan and clocca meaning "bell". A silent instrument lacking such a mechanism has traditionally been known as a timepiece.” Design and accuracy of clocks have evolved along with progression of technology and industry and even though their main
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