Analysis of the content in Aspirin Tablet
) Title: V3 Analysis of the content in Aspirin Tablet 2) Aim/Objective: To find out the mass of aspirin in each tablet by using back titration 3) Theory In this experiment, hydrolysis and back titration are carried out to determine the mass of the active ingredient aspirin in each aspirin tablet to see if it is the same as that stated on the package. Hydrolysis is a chemical process in which a molecule is cleaved into two parts by the addition of a molecule of water. Since aspirin (2-ethanoylbenzoic acid) can be readily hydrolysed using sodium hydroxide, forming the sodium salts of two weak acids, ethanoic acid and 2-hydroxybenzoic acid, and a water molecule, excess sodium hydroxide is used to react with aspirin in a conical flask initially, as illustrated in the following series of equations: CH3COOC6H4COOH(aq) + NaOH(aq)› CH3COOC6H4COO -Na+(aq) + H2O(l) CH3COOC6H4COO -Na+ (aq) + H2O(l) ? HOC6H4COO-Na+ (aq) + CH3COOH(aq) CH3COOH(aq) + NaOH(aq) › CH3COO-Na+(aq) + H2O(l) Overall reaction: CH3COOC6H4COOH(aq) + 2NaOH(aq)›HOC6H4COO-Na+(aq) + CH3COO-Na+(aq) +H2O(l) The hydrolysis is performed on a Bunsen flame to speed up the reaction. The kinetic energy of molecules becomes greater with an increase in temperature, colliding with each other faster. After warming for at least 10 minutes, all the 2-ethanoylbenzoic acid in the conical flask has reacted with sodium
To investigate how concentration affects the rate of reaction in reacting Calcium Carbonate and hydrochloric acid.
AIM: To investigate how concentration affects the rate of reaction in reacting Calcium Carbonate and hydrochloric acid. THEORY: The rate of reaction tells scientists how quickly a chemical reaction occurs. To find out the rate of reaction, we can measure how much reactant is used up in a certain time. On the other hand we might measure how much product is formed. Graphs are used to measure the rate of reaction at any given point in time this is called the instantaneous rate. The slope of the graph is the gradient and it tells us how quickly a reaction is going at one particular time. Before a reaction can take place, molecules or ions have to bump into each other and the collision must be a hard one (hard enough to bring about a bond breakage). Only a small fraction of the collisions, which take place, are violent enough to bring about a reaction, because not all particles have enough energy. This is called collision theory. To speed up reactions, we must make the particles collide more vigorously and more often. There are many ways you can increase the rate of reaction: . Increase the surface area 2. Increase the temperature 3. Introduce a catalyst 4. Increase the pressure 5. Increase the concentration In my experiment I am looking at concentration. As you increase the concentration of hydrochloric acid the rate of reaction increases because there are
An Experiment To Identify A Series Of Liquids
BACKGROUND THEORY ALKENES The alkene in this set of liquids is cyclohexene. It has the structural formula of CH2CHCHCH2CH2CH2. It has an intense, sharp smell. The test for alkenes is the addition of bromine water. In the event of an alkene being present, the bromine water, which is normally an orange-brown colour, will decolourise to leave a clear halogenoalkane. In this case, the halogenoalkane formed will be ,2 - dibromocyclohexane. The reaction is electrophilic addition or in this case, halogenation. Equation: CH2CHCHCH2CH2CH2 + Br2 ==> CH2CHBrCHBrCH2CH2CH2 Cyclohexene bromine 1,2 - dibromocyclohexene HALOGENOALKANES Bromoethane is the halogenoalkane in the set of liquids given. It is also known as ethyl bromide, and has an ether-like smell. Its structural formula is CH2CH2Br. The test for halogenoalkanes is to add aqueous sodium hydroxide, then warm with ethanolic silver nitrate solution. If there is a halogenoalkane present, a precipitate of silver bromide will be formed. In the case of bromide ions, a cream precipitate will form; chloride ions form a white precipitate, and iodide ions form a yellow precipitate. The reaction is nucleophilic substitution. Equation: CH3CH2Br + NaOH(aq) ==> CH3CH2OH + NaBr Bromoethane ethanolic silver nitrate 2-nitro-ethanol silver
Studies On Vitamin C Degradation in Fruit.
Studies On Vitamin C Degradation in Fruit. Introduction and background. Vitamin C is of vital significance in the metabolism of most organisms, however interestingly the primates including monkeys and man, guinea pigs and the Indian fruit bat are the only known higher species to be susceptible to the lack of the vitamin However micro-organisms do not form this chemical. In other words ascorbic acid is not synthesised within the cells of these species. Normally the liver is the site of ascorbic acid formation, but in birds, reptiles and amphibians the site of synthesis is the kidneys. The chemical is widely distributed in brain tissue at around 150mg/Kg, in the lens of the eye 250mg/Kg and in the adrenals 400mg/Kg. Tissue levels are highest at birth and greatly reduce in old age. A large percentage in any foodstuff is lost on storage or cooking. It is also known that addition of sodium bicarbonate to maintain the green colour of vegetable during cooking can destroy 70-90% of Vitamin C content The deficiency disease associated with this vitamin is known as scurvy. This is characterised by problems associated with connective tissues, including failure of normal bone formation in children, poor wound healing and increased capillary fragility leading to haemorrhage (especially in the skin, together with effects on teeth and gums. The minimum intake in infants to prevent scurvy
Investigate the effect of sodium carbonate on water.
Chemistry Coursework I am going to investigate the effect of sodium carbonate on water. I will use a sample of water, and with differing amounts of sodium carbonate dissolved in the water and I will see how much soap solution it will take to create a permanent lather. I will use a burette and pipette and such items to measure soap solutions and the volume of water (which stays constant) and to weigh the mass of the sodium carbonate, I will use a digital weighing scale with a dust shield. I am also going to record observations throughout the experiment and also try and keep the temperature readings using a thermometer to see what effect it has by observation or if the results are out of proportion during the experiment since that is one of the uncontrollable variables. Water with dissolved Na2CO3 Burette Weighing scales Conical Flask Conical Flask Sodium Carbonate Apparatus: * Burette for accurate soap solution volume * Pipette for accurate water volume * Pipette filler for filling the pipette * Weighing Scales for accurate mass of Na2CO3 in grams * Conical Flask and bung used for shaking the water, sodium carbonate and soap solution. * Filter Funnel * Filter paper * Clock The theory behind this experiment is that if you put more sodium carbonate in the water, the water will get softer and therefore there will be less soap needed to create a permanent
To investigate the reaction between Sodium Thiosulphate and Hydrochloric Acid.
Reaction Rates Aim: To investigate the reaction between Sodium Thiosulphate and Hydrochloric Acid. Prediction: I think that as the amount of Sodium Thiosulphate is decreased and the volume of water increased, the reaction time between it and Hydrochloric acid will increase. This is because when the concentration of a substance is increased, it reacts a lot quicker due to there being more particles that want to react with each other. Reactions can only happen when the reactant particles collide, but most collisions are not successful in forming product molecules. Water has been introduced in this experiment to vary the concentration. If there is more water in the experiment, the less concentrated the Sodium Thiosulphate will be, therefore slowing the reaction. ==>==> When Sodium Thiosulphate reacts with an acid, a yellow precipitate of sulphur is formed. Diagram: As you can see, the higher the concentration, the more collisions between particles will happen Variables: During the experiment I will keep the amount of Hydrochloric Acid the same and the total volume will always add up to 60cm3 to make it a fair test. I will change the amount of Sodium Thiosulphate from 50cm3 and decrease each time by 5cm3 and increase the amount of water to investigate whether concentration affects reaction time. I will take 2 sets of results to ensure that they are accurate. If 1 time taken
Finding the solubility of Ca(OH)2.
Finding the solubility of Ca(OH)2 Aim: To determine the solubility of Ca(OH)2. To carry out the aim of this experiment an experiment needs to be planned and carried out. I am given the information that the solubility of the Ca(OH)2 is between 1 to 1.5g per dm3. Also I am given a standard solution of 1M hydrochloric acid (HCl) which may have to be diluted to suit the measuring needs of the experiment. Apparatus: * 1g of Ca(OH)2. * Pipette 25cm3 * 2 x 500cm3 beaker * Conical flask 250cm3 * Burette * White tile * Burette stand * Stand * Indicator * 300cm3 of Hydrochloric acid- standard solution (concentration of 0.05M) * Distilled water * Filter Paper * Stirring rod * Funnel Method: * Add 1g of Ca(OH)2 to 300cm3 of distilled water in a 500cm3 beaker. Keep stirring the solution till the solid stops dissolving. This leaves a saturated solution. * Filter off the excess solid into another 500cm3 beaker using a damp filter paper (distilled water). * Repeat the filtration of the solution till there is no solid left. Making sure to stir the solution in between the filtrations and clean out the other beaker with plenty of water. * This should leave 300cm3 of Ca(OH)2 saturated solution which will be used in the titration experiment needed to find the concentration of the solution. * Use some of the Ca(OH)2 to rinse out the conical flask and the pipette. Use some
Which is the correct equation?
Chemistry Skill P: Which is the correct equation? Potassium nitrate (KNO3) is a crystalline, white compound which is prepared commercially by reacting potassium chloride and sodium nitrate. Its uses in industry range from acting as a food preservative, to use in the manufacturing of explosives and fertilisers. This plan is to test which of the following two equations are accurate in measuring the gas products formed from heating KNO3: * 2KNO3(s) ----------> 2K02(s) + 02(g) * 2KNO3(s) ----------> K20(s) + 2NO2(g) + 1/2 02(g) It is noticeable that a different number of moles of gas are produced on heating potassium nitrate in the two equations. To determine which is correct, a calculated amount of potassium nitrate will be heated, and the volume of gas given off will be measured. The number of moles of gas calculated from this volume will provide the answer. Equipment: * Gas syringe and holder * Retort stand and boss * Additional boss and clamp * Spatula * Glass test tube with attached delivery tube and bung * Heat proof matt * Bunsen burner * Glass weighing bottle Chemicals: * Powdered potassium nitrate Safety Precautions: * Wear safety glasses at all times to avoid potassium nitrate entering the eye. Should this occur however, immediately wash eyes with water for 10 minutes and seek medical help. * Clean up any spillages immediately. * Any skin
Steps for Solving Titration Problems
Term Explanation Volumetric analysis A quantitative technique used to analyse solutions using volumes of solutions. Burette Calibrated apparatus with a delivery tap at the base, used to deliver up to 50 mL of solution Pipette The analytical pipette is designed for accurate transfer of fixed volumes of solution. Common sizes include 5.0 mL, 10.0 mL, 20 mL, and 50 mL. A pipette bulb is used to draw up solution safely into the pipette. titrate To add the solution from the burette into the receiving flask while watching for a colour change. titre The volume of solution added from the burette to exactly reach the end-point. aliquot The accurate volume of solution transferred by pipette to the receiving flask. end point The point at which a colour change occurs. The solution added from the burette is usually just in excess. equivalence point The point at which the ratio of moles of reactants is equal to the ratio in the reaction equation; neither reactant is in excess. indicator The suitable acid-base indicator that changes colour at the end point. This indicator should be chosen carefully so that the end-point is as close as possible to the equivalence point. primary standard The substance used to make a solution of accurately known concentration. standardisation The process of determining the concentration of a solution by titrating it with a primary
To run the synthesis of calcium oxalate via the precipitate from solution containing calcium ion and oxalate ion.2. To do a thermo gravimetric analysis on calcium oxalate.3. Understand and practice the method of homogeneous precipitation
FACULTY OF SCIENCE ANG ENGINEERING CHEMISTRY LABORATORY UESC 1122 Experiment 23 Synthesis and thermal analysis of the group 2(IIA) metal oxalate hydrates DATE : 10 NOV 2005 Objective : . To run the synthesis of calcium oxalate via the precipitate from solution containing calcium ion and oxalate ion. 2. To do a thermo gravimetric analysis on calcium oxalate. 3. Understand and practice the method of homogeneous precipitation through this experiment. Introduction Thermo gravimetric analysis (TGA) is one of the common analytical thermal analysis techniques that widely use to determine the thermal profile and stability of compound. This is rather important in the industry. When the thermal profile of certain substance was know, it can be produce in large quantity by an accurate reaction with the lowest cost. With the TGA techniques, a sample of material is being heated, while the sample mass is recorded as a function of temperature. By doing so, the composition of the material is analyzed, both qualitatively (which components are present in the material) and qualitatively (how much of these components is present). In this experiment, synthesis and thermo gravimetric analysis of calcium oxalate has been carried out. Synthesis of calcium oxalate was done by the reaction between calcium ions and oxalate ion: Ca2+(aq) + C2O42-(aq) CaC2O4(s) In which prepared via
