F336- aspirin individual Investigation
Does Temperature Affect The Yield And Purity Of Aspirin? Contents Objectives ) Research using various sources on aspirin with reference to; history ,use in medicine and methods of synthesis 2) produce a sample of aspirin using a method found during research 3) Verify the presence of aspirin and use various method to measure the purity of the manufactured aspirin 4) Carry out investigation to see if temperature effects the yield and purity of aspirin Research History of aspirin 400 BC, Greece - Hippocrates recommended a brew made from willow leaves to ease the pain of child birth. 763, England - A reverend called Edward Stone was walking through a meadow in Oxfordshire while suffering from an acute fever. Stone removed a small piece of bark from a willow tree and nibbled on it. He was struck by its extremely bitter taste, as an educated man he knew that he bark from Peruvian cinchona tree (which has a similar taste) is used in the treatment of malarial fevers. He surmised that the willow might also have therapeutic properties. He gathered and dried a pound of willow bark and created a powder which he gave to about fifty people. It was consistently found to be a "powerful astringent and very efficacious in curing agues and intermitting disorders". He had discovered salicylic acid, the active ingredient in aspirin. 1828, Germany- Johann Büchner isolates pure
Comprehensive and Detailed Chemistry notes
. MUCH OF THE WORK OF CHEMISTS INVOLVES MONITORING THE REACTANTS AND PRODUCTS OF REACTIONS AND MANAGING REACTION CONDITIONS * outline the role of a chemist employed in a named industry or enterprise, identifying the branch of chemistry undertaken by the chemist and explaining a chemical principle that the chemist uses * identify the need for collaboration between chemists as they collect and analyse data Chemists usually work in teams. The needs for collaboration are: - The sharing of expertise. Not all chemists work in the same field. - There is a wider knowledge available - Incraeses validity and acuuracy of data and results - Time is saved since data is gathered and analysed in teamwork * describe an example of a chemical reaction such as combustion, where reactants form different products under different conditions and thus would need monitoring Once a reaction takes place, it is important to monitor the reaction. This is because if conditions in the reaction chamber are altered, harmful products may be produced and reaction wouldn't go to completion. Eg: Incomplete combustion - Incomplete combustion of octane: C8H18(l) + 9O2(g) › 3CO2(g) + 3CO(g) + 2C(s) + 9H2O(g) - CO is a poisonous gas which combines strongly with haemoglobin preventing transport of oxygen - Carbon is a pollutant and forms soot - Incomplete combustion occurs in poorly started
The aim of this experiment is to produce Aspirin. This is an estrification in which an alcohol reacts with an acid and a small molecule is often eliminated. The reaction takes place under a concentrated acid catalyst which speeds up the chemical reaction.
Contents Planning Page number * Background Information---------------------------------------- 3 * Aim---------------------------------------------------------------- 4 * Plan - (choices of equipment)--------------------------------- 5 - 15 - (risk assessment) * Synoptic grid----------------------------------------------------- 16 Implementing * Preparation of Aspirin------------------------------------------ 18 - 19 * Melting point determination---------------------------------- 20 * Forward titration------------------------------------------------ 21 - 24 * Back titration---------------------------------------------------- 25 - 28 Analysing * Calculations----------------------------------------------------- 30 - 35 * Conclusion------------------------------------------------------ 36 - 37 Evaluating * Uncertainty associated with measurements--------------- 39 - 46 * Limitations of methods-------------------------------------- 47 * References---------------------------------------------------- 49 Background Information Introduction (1) (2) Aspirin is member of a family of chemicals called salicylates. Aspirin the pain reliever also known by the chemical
Potassium permangonate
An Investigation into the Kinetics of the reaction between Potassium Permanganate and Oxalic Acid with a Sulphuric Acid Catalyst Aim The primary objective of my investigation is determining the orders of reaction for the oxidation of oxalic acid by potassium permanganate, with a sulphuric acid catalyst: 2 MnO4-(aq ) + 5 H2C2O4(aq ) + 6 H3O+(aq ) --> 2Mn2+(aq ) + 10 CO2(aq ) + 14 H2O I will find this by applying alterations to certain factors that affect the rate of the reaction, and observing which ones have a greater bearing. These factors will be the concentrations of each reactant and the catalyst, and also the temperature of the solutions at the time of reaction. I will consider: o What is the rate equation? o What is the order of reaction for each reactant? o What is the activation enthalpy of the reaction? Apparatus * 250 cm³ volumetric flasks * Bulb pipettes-10cm³, 25cm³, 50cm ¯³ * Teat pipettes * 100 cm³ beakers * Distilled water * Digital Thermometer * Water Bath * Colorimeter * Stopclock * Cuvettes Apparatus Descriptions and Justifications The 250 cm³ volumetric flasks have been designed to allow the preparation of solutions, with a very high degree of accuracy regarding both volume and concentration. I will be using class B flasks, which have a tiny error. These volumetric flasks have been calibrated at room temperature, so will be
Find the enthalpy change of combustion of a number of alcohol's' so that you can investigate how and why the enthalpy change is affected by the molecular structure of the alcohol.
Aim The aim is to find the enthalpy change of combustion of a number of alcohol's' so that you can investigate how and why the enthalpy change is affected by the molecular structure of the alcohol. Background Knowledge Combustion is principally the oxidation of carbon compounds by oxygen in air to form CO2 if there is a sufficient amount of oxygen. The hydrogen in a compound forms H2O. Combustion produces heat as well as carbon dioxide and water. The enthalpy change of combustion is the enthalpy change that occurs when 1 mole of a fuel is burned completely in oxygen. I can use an enthalpy cycle to work the combustion value out only if you have the right information. The energy contained in the bonds of the products is less than the energy contained in the bonds of the reactants. The difference in energy is released as heat. Energy releasing reactions are called exothermic reactions. Calorimetery is a way to determine the amount of heat produced in a reaction. Calorimeters are devices to measure heat released by a reaction. The temperature of the calorimeter increases as heat is released by the reaction. For any reaction to take place bonds must be broken and made Bond breaking requires energy whilst bond making releases energy. Bonds between different atoms require or release different amounts of energy when broken or made because they are different in
The aim of this experiment is to investigate the enthalpy change of combustion for a variety of alcohols and determine how the number of carbon atoms affects the combustion of the alcohol.
The enthalpy change of combustion of alcohols Aim The aim of this experiment is to investigate the enthalpy change of combustion for a variety of alcohols and determine how the number of carbon atoms affects the combustion of the alcohol. 'The standard enthalpy change of combustion is the enthalpy change when one mole of an element or compound reacts completely with oxygen under standard conditions. For example a pressure of 100 kilopascals, a temperature of 298 Kelvin, solutions must have a concentration of 1.0 mol/dm3 and also the reactants and products must be in the physical states e.g. solid, liquid or gas, that are normal for these conditions.'1. An example of a combustion reaction of methane is show below. CH4(g) + 2O2 CO2 (g) + 2H2O(l) Prediction & Development of problem I predict that the enthalpy change of combustion will increase as the number of carbon atoms within the alcohol increases. Alcohols form a homologous series. A homologous series is formed by molecules with different carbon chain lengths but with the same functional group and all have similar chemical properties. These aliphatic alcohols have the general formula CnH2n+1OH, (where n is the number of carbon atoms present in the molecule.) The alcohols are given names of the alkane with the corresponding number of carbon atoms with the final 'e' being replaced with 'ol'. Alcohols all have
investigating the amount of ascorbic acid present in fruit
Investigating the Amount of Ascorbic Acid Present in Fruits: Aim: To investigate the amount of ascorbic acid present in samples of fruit. Introduction: What is Ascorbic Acid and Why It Is Needed: Ascorbic acid is another name for vitamin C and is an essential vitamin needed for everyday life. Vitamin C is also soluble in water, which is important to humans since we are unable to synthesize our own ascorbic acid within the liver. It is also an antioxidant (which can help prevent cancer) and is added to foods to protect their colour and aroma. Furthermore ascorbic acid is used to prevent the oxidation of fats and oils by atmospheric oxygen, resulting in the development of rancid flavours. In addition ascorbic acid is vital for the production of collagen (intermolecular substance that gives bones, teeth and cartilage their structure). Other reasons why it is needed include: * Synthesis of bile acids * Maintaining skin elastic * Assists in iron absorption * Improves resistance to infection Deficient Amount of Ascorbic Acid: An insufficient diet of ascorbic acid should be best avoided to refrain from these symptoms such as: * Fatigue * Insomnia * Loss of appetite * Minor capillary bleeding In a very severe case: * Scurvy (in which the legs are shaped in an abnormal way). Using Titration to find out the Known Amount of Vitamin C: The titration method can be used
Chemistry Investigation - How does chain length affect: ∆Hcè for alcohols?
Chemistry Investigation - How does chain length affect: ?Hc? for alcohols? INTRODUCTION: The enthalpy of combustion is the overall energy change, when 1 mole of a named species reacts with the maximum amount of Oxygen in a combustion process. This must take place under the standard conditions, these being 298K and 1 atmosphere of pressure. Combustion is a process involving the breaking and subsequent making of bonds. The breaking of bonds is an endothermic process and the making of these same bonds is exothermic. The difference between the energy in and out dictates that the combustion of alcohols is exothermic overall, as Ein < Eout. Due to the fact that the combustion of alcohols is an exothermic reaction, the products are at a lower energy level than the reactants and therefore the difference in energy (enthalpy) is always negative. The experiment of alcohol combustion is necessary, because it is otherwise impossible to derive enthalpy values. They must be derived from the temperature change in a chemical reaction. This experiment and the enthalpy information it offers is useful in helping us to understand the efficiency of fuels and how we can use these fuels favourably in the chemical industry. AIM: To determine through a mixture of experimentation and theoretical enthalpy mathematics, the effect of chain length on the combustion enthalpy for different alcohols.
Enzyme catalysed decomposition of hydrogen peroxide
Objective The purpose of my experiment is to determine the effect of different concentration of copper Hydrogen Peroxide on the activity of catalase and the production of oxygen. Background Knowledge Catalase is an enzyme which is globular protein - the secondary protein structure is folded into a spherical or globular shape. Hydrogen bonds, ionic bonds, disulphide bridges and hydrophobic interactions (between groups of amino acids) maintain the specific three dimensional shape of the enzyme. This specific 3D shape is very essential for the functioning of enzymes. The part of the enzyme which binds with the substrate is called the active site. The shape of the active site differs from one enzyme to another. This makes the enzyme react only with a specific substrate, which fits the active site. Enzymes also lower the activation energy and provide an alternate (lower energy) pathway for the reaction to proceed. Thus the rate of reaction speeds up (catalyst). Figure 1 The enzyme active site binds to hydrogen peroxide (substrate) and decomposes it to oxygen and water. Catalase (Yeast) Hydrogen Peroxide Water + Oxygen 2H2O2 2H2O + O2 Figure 2 There are many factors which affect the activity of enzymes; the concentration inhibitor is one of the factors which have a massive effect the activity of enzyme. An enzyme
What are alcohols?
What are alcohols? Alcohols are a specific group of substances that are hydroxyl derivatives of hydrocarbons but more explicitly they are types of fuel. A fuel is a substance (e.g. methane) that readily undergoes combustion (the combustion of a substance involves its reaction with oxygen and the release of energy) and gives out large amounts of energy. The combustion of fuels is usually an exothermic reaction. The distinction between alcohols and other fuels, such as methane, is that alcohols are a homologous series of compounds that contain the -OH group of atoms as the functional group. The functional group in a molecule is the group of atoms within the structure that determines the characteristic reactions of that substance. All the earlier, smaller alcohols have a neutral pH, and are colourless liquids that do not conduct electricity. The general chemical structure of an alcohol is as follows: CnH(2n+1)OH By far the most well known alcohol is ethanol, which often goes by the common name of alcohol itself. Its chemical formula is C2H5OH. It is produced in industry by reacting ethene and steam together. They are first compressed to 60 atmospheres and passed over a catalyst (immobilised phosphoric(v) acid) at 300ºC. 300ºC, 60 atmospheres ethene + steam -------› ethanol phosphoric acid fuel + oxygen --› carbon dioxide + water and replacing the fuel with the
