Determining the concentration of acid in a given solution
Determining the concentration of acid in a given solution Planning 4 I have been given a sample of sulfuric (VI) acid solution with a concentration between 0.05 and 0.15 mol dm-³. I am going to find out the accurate concentration of the sulfuric acid. To find out the concentration of the acid I will react it with a known volume and concentration of a base and see how much base was needed to neutralise the acid. The acid is a strong acid which means that I know all the H+ ions have been disassociated and are in the solution. The H+ ions will react with the OH- ions in the alkali which will neutralise the solution. I am provided with solid, hydrated sodium carbonate with the formula Na2CO3·10H2O.1 This is a readily available base and I can dilute it down to achieve the concentration I want to react with the acid. The formula of the reaction that will take place is H2SO4 (aq) + Na2CO3 (aq) --> Na2SO4 (aq) + CO2 (g) + H2O (l) So 1 mole of H2SO4 reacts with 1 mole of Na2CO3. A titration will give me the most reliable and accurate results with the available equipment. To do my titration I will need: A Burette 7 I will need a burette to add the sodium carbonate to the sulfuric acid solution. The burettes provide me with very accurate results of volume of solution added. The class set of burettes measure 50cm3. I want to do a titration
Investigating the forces acting on a trolley on a ramp
Physics coursework Investigating the forces acting on a trolley on a ramp Contents Page 3 -> Method Page 4 -> Theory Page 7 -> Results Page 9 -> Error Page 18 -> Appendixes Method The aim of the investigation was to investigate the forces acting on a trolley as it rolled down a ramp, and also to investigate the factors which may contribute to the results. To do this, a trolley and a ramp set at a variety of angles of incline were used, and then, using a light gate, the speed at which the trolley was moving when it passed through the light gate was calculated. The variables were the starting distance of the trolley in relation to the light gate and the angle of the ramp. Firstly, the equipment was set up as in fig. 1. The trolley was then run down the ramp with a piece of card attached to the side. This card was of a known length and could hence be used to calculate the velocity at which the trolley was moving. While the light gate did actually calculate the velocity, it only gave the answer to 2 decimal places, whereas it gave the time to 2 decimal places. Furthermore, the light gate calculated the velocity with the assumption that the card was exactly 100mm, whereas when the card was actually measured, this was a value closer to 102mm (±0.5mm). Next, after the trolley had passed through the light gate, the information from that 'run' appeared
UV-Visible Spectrophotometry
Name: Chu Ka Ki Student No.: 50555542 Group: 1 Date: 17-02-2005 Experiment: 2 BCH 2004 Principle of Analytical Chemistry Lab Report (Report One) Title: UV-Visible Spectrophotometry Aim: To determine phosphate composition in cola beverages by UV-Visible spectrophotometry and pH titrimetry. Introduction: UV-Visible spectrophotometry is one of the most important methods for the chemical analyze. Ultraviolet-Visible spectroscopy or Ultraviolet-Visible spectrophotometry (UV/VIS) involves the spectroscopy of photons (spectrophotometry). It uses light in the visible and adjacent near ultraviolet (UV) and near infrared (NIR) ranges. In this region of energy space molecules undergo electronic transitions. The method is used in a quantitative way to determine concentrations of an absorbing species in solution, using the Beer-Lambert law: where A is the measured absorbance, I0 is the intensity of the incident light at a given wavelength, I is the transmitted intensity, L the length of the cell, and c the concentration of the absorbing species. For each species and wavelength, ? is a constant known as the extinction coefficient. The absorbance A and extinction ? are sometimes defined in terms of the natural logarithm instead of the base-10 logarithm. Methodology: Colorimetric Analysis: At the beginning, 4cm3 decarbonated cola was transferred into a 100cm3
Sensing project
Sensing project Project brief A new greenhouse is being developed for gardeners who are concerned about overheating plants in their current greenhouses. The new greenhouse has been built with opening windows but occasionally the windows of the greenhouse slips fully open and allow all of the trapped heat in the greenhouse to escape quickly. This is a major concern for serious gardeners. The test is to develop a sensing circuit that will sense whether the windows are fully open, so a gardener can be alerted of the problem. Introduction To begin we must know what a sensor is. A sensor is an electrical component, which produces a signal in response to alteration in its surroundings, this maybe an alteration in a physical variable or by movement of objects. The sensor planned for the sensing circuit ensuring the windows are not fully open is a rotary potentiometer. A rotary potentiometer is a component, which has three terminals. When the angle of rotation is changed on the component's arm then the potential difference (often called voltage) is also changed. Once the voltage reaches a specific point a separate circuit could activate an alarm showing that the window has slipped and is fully opened. The potential difference is the difference between potential energy between two separate points. Alternatively a different sensing circuit could be used. A circuit with
Analysis of Two Brands of Commercial Bleaches
PLK TANG YUK TIEN COLLEGE ADVANVED LEVEL CHEMISTRY (TAS) EXPERIMENT 3 Analysis of Two Brands of Commercial Bleaches Objective To determine the concentration of sodium chlorate(I) (NaClO) in two commercial bleaches and compare the two bleaches on both concentration and price. Procedures . 10.0 cm3 of the bleach "KAO" was pipetted into a clean 250 cm3 volumetric flask. It was made up to the mark using deionized water. 2. 25.0 cm3 of the diluted solution was pipetted into a conical flask. 3. 10 cm3 of 1 M potassium iodide solution and 10 cm3 of dilute sulphuric acid was added into the conical flask also. 4. The mixture in the conical flask was titrated against the 0.0992 M sodium thiosulphate solution. 5. Three drops of freshly prepared starch indicator are added into the conical flask when the reaction mixture turned pale yellow . 6. The mixture was titrated to the end-point. 7. At the end point, the solution turned from dark blue to colourless. 8. Steps (1) to (7) were repeated with another bleach "LION" Results Concentration of standard sodium thiosulphate solution : 0.0992M Brand 1 Trade Name : KAO Bleach Price : $7.33per dm3 ($11/1500mL) Trial 2 Final burette reading / cm3 1.90 23.40 35.00 Initial burette reading / cm3 0.20 1.90 23.40 Volume of Na2S2O3 / cm3 1.70 1.50 1.60 Brand 2 Trade Name : LION Price : $6.67per dm3
Biology - Most effective way of reducing blood pressure
The Problem - High Blood Pressure has always been the cause of Stokes and CHD (Coronary Heart Disease) leading to a Heart Attack or even CVD (Cardio Vascular Disease). It indeed is the biggest killer in this developed world. High blood pressure directly implicates on the blood vessels, the veins and the arteries. When blood pressure increases, it constantly damages the arteries, whereas arteries already have narrow lumens. When the artery wall gets damaged, by the high blood pressure putting an extra strain on the layer of cells (Endothelium), there are white blood cells moving to the damaged area, and they accumulate cholesterol from the blood. This cholesterol builds a deposit, known as atheroma. This is an inflammatory response. There also are calcium salts and fibrous tissue building up at the site, resulting in a hard swelling called a plaque on the inner wall of the artery. This hardens the artery. Those plaques case the artery to become narrower, which makes it more difficult for the heart to pump blood around the body, in other words, there is a rise in blood pressure plus there now is a positive feedback building up as the process continues. A Blood Clot may also form there and even block the artery completely, minimising the blood supply, containing oxygen, to the heart which can lead to a heart attack and major CHD(s). {Results show that over 7 million people had
Investigation on the size of Limpets.
Investigation on the size of Limpets Abstract: During my preliminary investigations, I established that sheltered and exposed rocky shores, differed immensely in their size of Limpets. Thus I was inspired to compare the size of Limpets on the sheltered rocky shore, Frenchman's Steps. The background knowledge and preliminary work enabled me conclude the following hypothesis; there will be a statistically significant difference between the size of limpets found on the sheltered rocky shore at two different vertical heights. I decided to look at 3M and 6M above chart datum for my investigation, as looking at the profile graph (appendix) the number of limpets was high at that chart datum. Aim: To determine if there is a difference in the size of limpets at two heights in there Vertical range. Scientific Background Limpets are animals that belong to the family Patellidae, subclass Prosobranchia of the phylum Molluscs. They have a strong, conical shell composed mainly of calcium carbonate, protecting the internal tissue, underneath which is a sucker, also known as the limpet foot, which allows limpets to adhere to rock surfaces, as shown in the photographs. Limpets are usually immobile unless they are foraging and so zonation is less apparent. As can be seen from the pictures above, limpets have a hydrodynamic shape so that resistance to water flow is reduced. This
Deducing the quantity of acid in a solution
Sofia Gaggiotti Chemistry coursework: Deducing the quantity of acid in a solution 20/03/2008 Index Aim and Background information 3 Hazards 3 Protection 4 Method 5 Previous calculations 5 Making the Solution 6 Equipment needed 6 Quantities of materials needed 8 Procedure 8 Making the Titration 9 Equipment needed 10 Procedure 13 References 15 Results and calculations 16 Evaluation 19 Chemistry coursework: Deducing the quantity of acid in a solution Aim and background information The aim of this experiment is to find how to develop and determine an accurate, precise and reliable concentration of an acid rain solution. 1 To do this, we are going to make first a solution of sodium carbonate with distilled water and then a titration in order to calculate the concentration of sulphuric acid in a solution. Solution: a solution is a homogeneous mixture composed of two or more substances. In this mixture, a solute is dissolved in a solvent. Solutions are characterized by interactions between the solvent phase and solute molecules or ions that result in a net decrease in free energy. 2 Titration: a titration is a laboratory technique by which we can determine the concentration of an unknown reagent using another reagent that chemically reacts with the unknown. At the equivalence point (or endpoint) the unknown reagent has been reacted with the known reagent.
The Human Genome Project
Amira Nicola January, 2001 The Human Genome Project The Human Genome project is a scientific research effort to analyse the DNA of human beings and that of several other types of organism. The project began in the United States in 1990 under the sponsorship of the U.S. Department of Energy and the National Institutes of Health. It was scheduled to be completed in 15 years. The project's goal is to identify the location of every human gene and to determine each gene's precise chemical structure in order to understand its function in health and disease. In the nucleus of every cell in the human body, there are 23 pairs of chromosomes, each of which is composed of several genes. Genes are discrete stretches of nucleotides that carry the information the cell uses to make proteins. The most important component of a chromosome is the single continuous molecule of DNA. This double-stranded molecule, which is shaped as a double helix, is composed of linked chemical compounds known as nucleotides. Each nucleotide consists of three parts: a sugar known as deoxyribose, a phosphate compound, and any one of four bases-adenine, thymine, guanine, or cytosine. These parts are linked together so that the sugar and the phosphate form the two parallel sides of the DNA ladder. This double-helical structure of the DNA molecule was discovered Watson and Crick in 1953, for
The Effect Of Temperature on the Respiration Of Yeast.
The Effect Of Temperature on the Respiration Of Yeast Introduction: - I am going to find out how temperature effects the respitory action of yeast. I am going to do this by using six different temperatures, 25oC, 30oC, 35oC, 40oC, 45oC and 50oC and a solution called TTC which is absorbed by the yeast cells turning them pink when hydrogen is removed from the metabolic pathway by the dehydrogenase enzyme. Background Information: - Yeast: - Yeast is unicellular fungus that buds profusely under favourable conditions. They are classified as sac-fungi (Ascomyctes) even though they are unicellular. Yeast is common in areas where there is sugar because of this they are given the name saccharomyces (Sugar fungi). They grow on the surface of fruits, in the nectar of flowers, in sap excluded from trees, in the soil and in fresh water. Yeasts are used in all sorts of arrears such as alcoholic fermentation (fermentation is the name given only to the anaerobic respiration of yeast) to baking bread. Yeasts are of a great economic importance and are yeast for biochemical research for example in respiration and enzymes. Yeast exists as Diploid or Haploid cells and divides by mitosis and meiosis. Yeasts are not plant or animal because they do not photosynthesise and they do not have any chloroplast. Yeast is a saprophyte. This is an organism, which obtains its nutrients from dead or
