Anion Test- Testing for negative ions in solutions.. Applied science unit 3 (AQA)
Anion Test- Testing for negative ions in solutions. Equipment: * Pipette * Test tube * Test tube rack * Goggles * Chemicals: Chloride, Sulphate, Carbonate, Dilute nitric acid, Silver nitrate solution, Hydrochloric acid, Barium chloride solution Hypothesis: I will test unknown solutions to find out if they are a Sulphate, Carbonate and Chloride. I would check for the negative ions in order to check for substance present. Method: To start, first of all I would design a results table to record my results in during the experiment, then I would put on my goggles this is to ensure my safety whilst handling hazardous/dangerous substances such as Chlorides. Then I would collect the correct equipment needed for this experiment this includes collecting test tubes, chemicals etc. When I have collected my equipment then I would set it all up such as putting my test tubes in the test tube holder, I would use a pipette to get the chemicals and put them in the test tube for testing. Then I would start the experiment and doing the tests, for example if I was to test for a Chloride I would first add a few drops of dilute Nitric acid then add a few drops Silver nitrate solution. The results that I get I would then record them in my results table. Risk Assessment: Name of hazard Hazard Safety Precautions Emergency action Risk level (Low/Medium/High) Image Pipette Pipettes
Flame Test Experiment
Flame Test Flame tests are used to identify the presence of a specific metal within a substance. Metals change the colour of a flame when they are heated, different metals give different colors. Flame tests are useful for confirming the results of a precipitate test. For example, an unknown solution that produced a pale blue precipitate with sodium hydroxide solution, and a green-blue flame test, must contain a copper compound. The test helps confirm which Metal it is. http://faculty.sdmiramar.edu/fgarces/labmatters/instruments/aa/Pic_AAS/flameTest.gif To identify an alkali metal, a flame test must be used instead of a sodium hydroxide precipitate test. This is because the alkali metals do not form precipitates with sodium hydroxide. Science behind flame tests By providing heat energy (flame) to the substance, the electrons within the substance gain a higher energy level from ground state energy; this is due to the heat which is provided. As the energy increases the electrons become unstable and begin to move around more, when the electrons move back to state energy the energy taken in is given out within specific wavelength which gives out different colours. Depending on the substance, the colours of the flame vary which is then measured using the emission spectrum.
The purpose of this experiment was to prepare a sample of Aspirin and measure its boiling point
2th October 2015 Preparation of Aspirin Abstract The purpose of this experiment was to prepare a sample of Aspirin and measure its boiling point. Reacting salicylic acid with acetic anhydride in excess with the presence of a catalyst sulphuric acid. Through a sequence of heating, filtering and recrystallizing the end product of making aspirin was positive and the measuring of its boiling point was successful. The sample was purified and the percentage yield was calculated to be 61.2% and to measure the purity of the sample the melting point was considered which came to be 122°c. Introduction The chemical name for Aspirin is Acetylsalicylic acid. Aspirin is known to relieve pain and is an over the counter drug. Salicylic acid was first found in the bark of the willow tree, which used to be used for treating fever and a variety of illnesses. However scientists soon began to realise that the acid used to thin the stomach lining and burn throats. (Ling, 1994) Not long after a German scientist, Felix Hoffman, derived a pain reliever that did not produce the same side effects as salicylic acid, and is credited for the finding of Aspirin. (Ling, 1994) Uses of Aspirin Another use of aspirin is people having to take it to thin the blood, which reduces the chance of unnecessary blood clots to form; therefore in the long term taking an aspirin everyday will prevent heart attacks
The periodic table
The periodic table The periodic table is the single most important document for chemists. Scientists have attempt to organize the elements in some sort of logical order for centuries. The most important chemist in history was Dmitri Mendeleev as he was the first scientist who made the periodic table look as the one we are use today. The French chemist Antione- Laurent de Lavoisier(1743-1794) compiled the first extensive list of elements in 1789. The list of element included oxygen, nitrogen, hydrogen, phosphorus, zinc mercury and sulphur. Before Antione-de Lavoisier people have known about basic chemical elements such as gold, silver, and copper from antiquity, as these can all be discovered in nature in native form and are relatively simple to mine with primitive tools. Aristotle, a greek philosopher, theorised that everything is made up of a mixture of one or more of four elements. They were earth, water, air, and fire. This was more like the four states of matter: solid, liquid, gas, and plasma, though he also theorised that they change into new substances to form what we see. In the nineteenth century the first recognizable Periodic Table was pieced together by comparing properties of different elements. At least 47 elements were discovered, and scientists began to see patterns in the characteristics. In 1828 Jakob Berzelius published a table of atomic weights and
sulphuric acid is dibasic
Demonstrating that sulphuric is dibasic: Aim: The aim of my plan is to demonstrate that sulphuric acid is dibasic. Introduction: Acid is a substance that reacts with a base to form a salt and water similarly a base is a substance that reacts with an acid to form a salt and water. "Lewis (a scientist) states that an acid is a compound that accepts a pair of electrons from a base and a base is a molecule or an ion that donates a pair of electrons to an acid. Acids taste sour and are corrosive and bases are slippery". ? Acid + Base › Salt + Water Acid + Metal › Metal Salt + Hydrogen gas Prediction: I predict that sulphuric acid, H2SO4 is dibasic because it forms two hydrogen (H+) ions in an aqueous solution. It is the molecule of sulphuric acid which changes to sulphate ions (SO42-) and hydrogen ions (H+) when dissolved in water. However, hydrochloric acid is monobasic as it only forms one hydrogen (H+) ion in an aqueous solution. To prove this, I am going to carry out two different experiments that involve a titration and collection of a gas. I assume that it should require me half a volume of sulphuric acid to neutralise sodium hydroxide, NaOH than HCl in titration. In the collection of gas, I expect to collect double the volume of gas when metal reacts with H2SO4 than that of produced in the reaction with HCl. Apparatus: Titration Equipment: Quantity: Reason
relative atomic mass of lithium
Determination of the Relative Atomic Mass of Lithium To find out the relative atomic mass of lithium I am going to use two methods. In Method 1 I will use the volume of hydrogen produced as lithium reacts with water. In method 2 I will titrate the lithium hydroxide which is the solution formed from my first experiment. METHOD 1 Table of results Mass of Lithium used (g) 0.08 Initial volume of water in measuring cylinder (cm3) 320 Final volume of water in measuring cylinder (cm3) 148 Volume of hydrogen gas produced (cm3) 172 Treatment of results The equation below shows lithium reacting with water in method 1. 2Li(s) + 2H2O(l) 2LiOH(aq) + H2(g) This equation will help me deduce the number of moles used. The following formula can be used to determine the number of moles of hydrogen gas produced. No of moles = volume 24000 No of moles of hydrogen = 172cm3 24000 = 0.00716 moles Looking at the equation it shows that for every 2 moles of lithium reacted, 1 mole of hydrogen is produced. This means the number of moles of hydrogen must be multiplied by 2 in order to find the number of moles of lithium. No of moles of lithium = 0.00716 x 2 = 0.01432 moles = 0.0143 moles (3 significant figures) Now that I have figured out the number of moles of lithium, I can work out the relative atomic mass of lithium by
Paper chromatography
Introduction It is suspected that a rival company producing felt tip pens is stealing ideas for new colour from primary colour, a leading felt tip pen manufacturer. The company requires proof before it starts making allegations and requires you to devise a test to determine whether the colours have been stolen. Somebody on the inside of the rival company has supplied the company with same prototype from the rival company for you to test whether the rival felt tip pen manufacturer is stealing ideas for new colours from the other company. Aim The aim of this coursework is to find if the rival company is stealing the other company's new idea. To determine if they have stolen news ideas for a new felt tip, I well perform to simple tests however effective (paper chromatography and thin layer chromatography). I well reform tests on the prototype and the company's felt tip to see any simulates. Paper chromatography Paper chromatography is one method for testing the purity of compounds and identifying substances. Paper chromatography is a useful technique because it is relatively quick and requires small quantities of material. Paper chromatography is an analytical technique for separating and identifying compounds that are or can be colored, especially pigments. This method has been largely replaced by thin layer chromatography, however it is still a powerful teaching
Analysis of Aspirin tablets
Laboratory report 7 - Analysis of Aspirin Tablets Name: Leung Dik Ka (14) Name of partner: Lee Wai Chi Date: 19/11/2008 Title of the experiment: Analysis of Aspirin Tablets Aims: To analyze the amount of the active ingredient in different commercial brands of aspirin tablets is carried out, to see whether the manufacturers' claims are justified. Introduction Pharmaceutical manufacturers are required by law to state on the packaging the amount of each active ingredient in their products. In this experiment a consumer survey on the amount of the active ingredient (2-ethanoyloxybenzoic acid, or o-acetylsalicylic acid) in different commercial brands of aspirin tablets is carried out, to see whether the manufacturers' claims are justified. 2-ethanoyloxybenzoic acid can readily hydrolyzed, using a known excess of sodium hydroxide, into the sodium salts of two weak acids, ethanoic acid and 2-hydroxybenzoic acid. The excess amount of sodium hydroxide is then estimated by a back titration with standard sulphuric(VI) acid. The equation for the hydrolysis reaction is: CH3CO2C6H4CO2H + 2NaOH(aq) --> CH3CO2Na (aq) + HOC6H4CO2Na (aq) + H2O (l) Phenol red (pH range 6.8-8.4) is most suitable for this titration due to the presence of the salts of two weak acids, though phenolphthalein is also satisfactory for the present purpose. Procedure [Hazard Warning: 1.0M sodium hydroxide
Esters investigation.
Esters Esters are compounds formed from the reaction between alcohols and acids. Esters are usually derived from carboxylic acids A carboxylic acid contains the -COOH group, and in an ester, the hydrogen in this group is replaced by a hydrocarbon group of some kind. This could be an alkyl group like methyl or ethyl, or one containing a benzene ring like phenyl. Example of esters: ATP, it is a phosphate ester. Fats and oils. Fats and oils are tri-esters of glycerol, propane 1, 2, 3 triol, with carboxylic acids Glycerol Fats usually come from land animals e.g. butter. Oils usually come from marine animals and from the vegetable kingdom e.g. sunflower oil. The difference between a fat and oil is simply in the melting points of the mixture of esters they contain. If the melting points are below room temperature, it will be a liquid - oil. If the melting points are above room temperature, it will be a solid - a fat. The lower melting temperature oils tend to replace fats in marine animals e.g. whales, because fats would be too viscous or solid at sea temperatures. Fats contain mainly saturated acids such as: * Hexadecanoic acid: C15H3CO2H, which is commonly known as palmitic acid. CH3 (CH2)14 COH * And octadecanoic acid: C17H35CO2H, which is commonly known as stearic acid. CH3 (CH2)16CO2H While oil contains a high proportion of unsaturated acids such
Scientific Practical Techniques
BETC National Diploma in Applied science/ Medical Science Scientific Practical Techniques Assignment number one Task 2 ) For this task I have done four different investigations, which is Hook's law, pH four unknown liquids, examine voltage, current change and growing yeast culture. Hook's law Hook's law given the relationship between the force applied to an unscratched spring and the amount the spring is stretched when the fore is applied. The purposes of this experiment is to see when we apply a force what will happen to the spring, therefore when we apply a force to a spring it will stretches, and if we apply double force it will stretches twice as much. I performed this experiment to determine how the extension of a spring varies with the stretching force. A spring is hung vertically from a fixed point and a force is applied in stages by hanging weights from the spring. The apparatus is set up as shown above. For the purpose of the experiment I used different gram 50 to 400 gram, and the extension of the spring I measured it metres. To start the experiment first I measured the unloaded length of the spring without touching, and then add the 50g loads, doing the same one at a time for all loads and measure the length of the stretched spring, and I recorded the results in the table. Load/ g Extension /mm 0g 0mm 50g 95mm 00g 30mm 50g 60mm 200g 90mm