Universaalindikaatori värviskaala (1)

Sarnased õppematerjalid

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HCl lahus

Aim of the work The determination of the concentrations of acid and base solutions through titration. Used compounds HCl solution with an unknown concentration. NaOH solution with a known accurate concentration, indicators phenolphthalein (ff/pp) and methyl red (mp/mr). Equipment Conical flasks (250 cm3), 2 burettes (25 cm3), pipette (10 cm3). Procedure A. Determining the concentration of a hydrochloric acid solution through titration 1. To determine the concentration of the acid solution take the NaOH solution with a known concentration (the standard solution) and pour it into the burette (α in figure 2.2). See that there are no air bubbles near the tip. Fill the burette until the 0-point of the scale. When measuring the level of the solution keep your eyes at the same level with the liquid level. The lower edge of the liquid level has to be at the 0 calibration mark (see figure 2.1). Work solutions are

Keemia ja materjaliõpetus

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Acid Rain

Acid Rain Acid rain is any precipitation that is unusually acidic. It possesses elevated levels of hydrogen ions(it has low pH level). Acid rain is caused by emissions of carbon dioxide, sulfur dioxide and nitrogen oxides, which react with water molecules. Distilled water(doesn't contain CO 2), has pH level 7. Liquids with pH level less than 7 are acidic, liquids with pH level greater than 7 are alkaline. Unpolluted rain has a pH level over 5.7, so it is slightly acidic. Affected areas Places significantly impacted by acid rain around the globe include most of eastern Europe from Poland northward into Scandinavia, the eastern third of the United States and southeastern Canada. Other affected areas include the southeastern coast of China and Taiwan Causes · It is caused when sulfur dioxide and nitrogen oxides are released into the air. In the atmosphere they react with water, oxygen and other chemic

Keemia

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Acid rain

Miina Härma Gymnasium Acid Rain Report Compiler: Teisi Timma 8a Teacher: Esther Linask Tartu 2009 Acid Rain Acid rain is rain consisting of water droplets that are unusually acidic because of atmospheric pollution - most notably the excessive amounts of sulfur and nitrogen released by cars and industrial processes. Acid rain is also called acid deposition because this term includes other forms of acidic precipitation such as snow. Acidic deposition occurs in two ways: wet and dry. Wet deposition is any form of precipitation that removes acids from the atmosphere and deposits them on the Earth's surface. Dry deposition polluting particles and gases stick to the ground via dust and smoke in the absence of precipitation. This form of deposition is dangerous however because precipitation can eventually wash pollutants into streams, lakes, and rivers. Acidity itself is determ

Geograafia

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Soil microflora

Estonian University of Life Sciences Report on Soil Microflora By Katrin Vares Tartu 2013 Introduction The purpose of this report is to define soil microflora and establish the importance of it. Since the microorganisms clearly play an important role in preserving the balance of life, the next objective is to look into factors that influence this balance. Natural conditions and cultural impact could be considered as the variables that correlate the most with the activity and composition of microflora, hence some of the natural and cultural factors will be looked into a little more in detail. Definition, composition and importance of microflora Saunders Comprehensive Veterinary Dictionary (2007) cited by the online medical dictionary (2013) defines living microorganisms as that small that they can be seen only with a microscope and that maintain a more or less constant presence in a particular area that includes bacteria, vir

Inglise keel

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Sagedamini esinevad korrosioonid

Aim To familiarize oneself with some more common instances of corrosion. Reagents Hydrochloric acid 0.1 M; sulphuric acid 0.1 M; zinc and aluminium granules; copper wire; solution of copper(II) sulphate; solution of copper(II) chloride; solution of iron(II) sulphate; solution of potassium hexacyanoferrate(III); zinc-plated iron sheet; tin-plated iron sheet; iron paper clips; solid NaCl; urotropin. Equipment Test tubes, small beaker (50 cm3), centrifuge tube. Experiments 1. Making of a galvanic pair 1.1. Place a zinc granule on the bottom of the centrifuge tube and pour solution of hydrochloric acid on top. Write down the equation of reaction which occurs. Which compound is the oxidant, which is the reductant? Zn+2 HCl ZnCl 2 + H 2 -¿ H 2 Oxidant is H: +¿+2 e ¿ 2 H¿ 2+ ¿ ¿ Reductant is Zn: -¿ Zn

Keemia ja materjaliõpetus

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Kraanivee kareduse määramine tiitrimise teel

Aim Determination of total and carbonate hardness of tap water using titration technique. Eliminating total hardness with a Na+ ion-exchange softener. Reagents 0.1 M hydrochloric acid, 0,025 M and 0,005M trilon-B solution, buffer solution (NH4Cl + NH3∙H2O), indicators methyl red (mr) or methyl orange (mo) and chromogen black ET-00. Apparatus Conical flasks (250 ml, 500 ml), measuring cylinder (25 cm 3), burette (25 cm3), pipettes (100 cm3). Experimental Procedure A Determination of carbonate hardness 1. Rinse the 100 cm3 pipette 2...3 times with a small amount of the test water. Wash the conical flask with distilled water. Pipette 100 cm 3 of the test water and transfer it into the conical flask, add 3...4 drops of indicator mo or mr. 2. Prepare the burette – remove any air bubbles from the nozzle and fill with 0.1 M hydrochloric acid till zero (The lower meniscus has to coincide with the scales 0-notation). 3. Titrate with a 0.1 M hydrochloric acid solution, while swi

Keemia ja materjaliõpetus

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Aniliini riskianalüüs (eng)

Tallinna tehnikaülikool Riski- ja ohutusõpetus keemiatööstuses Referaat: Kemikaali riskianalüüs Aniliin Õppejõud: Karin Reinhold Üliõpilane: Kood: 000000 Tallinn 2012 1. Introduction Aniline (also known as phenylamine or aminobenzene) is an organic compound with the formula C6H5NH2. Consisting of a phenyl group attached to an amino group, aniline is the prototypical aromatic amine. The largest application of aniline is for the preparation of methylene diphenyl diisocyanate. The majority of aniline serves this marke

Riski- ja ohuõpetus

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Capillary electrophoresis i.k.

Tallinn University  Natural and exact sciences  Molecular Biochemistry and Ecology                  Maria Gnidenko     Capillary electrophoresis     Essay                   Supervisor: Kert Martma                 Tallinn  2015    Table of contents Acronyms and symbols used  Introduction  History and development  Physical basis and principle of separation  Elektrophoresis  Electroosmotic flow  Separation process  Electrodispersion  Various methods of separation  Capillary zone?

Instrumentaalanalüüs

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