Importance of Chemical Analysis in day to day life

The knowledge of chemical analysis today has become important not only for scientists in their research but in fact bears influence in our daily routine as well. To recognize and classify these uses, we have to first understand, what is chemical analysis?Chemical AnalysisChemical Analysis is a body of procedures and techniques used to identify and quantify the chemical composition of a sample of substance.1 It may be said as a collection of all the techniques required to obtain any chemical information about a particular substance. There are two branches in analytical chemistry: Qualitative analysis and Quantitative analysis. Qualitative chemical analysis is used to identify a particular element/compound in a sample of substance. Quantitative chemical analysis consists of determining the quality or concentration of a specific sample of substance. Thus for example, determining whether a sample of salt contains the element chlorine is a qualitative analysis; measuring the percentage by weight of any chlorine in the sample is a quantitative analysis.

Qualitative AnalysisQualitative analysis is the determination of those elements and compounds that are present in a sample of unknown material. It is a method of analytical chemistry which seeks to find elemental composition of inorganic compounds. It is mainly focused on detecting ions in an aqueous solution, so that materials in other forms may need to be brought into this state before using standard methods. The solution is then treated with various reagents to test for reactions characteristic of certain ions, which may cause color change, solid forming and other obviously visible changes. A wet method qualitative analysis of inorganic ions proceeds by separating the ions into groups by selective precipitation reactions, isolating individual ions in the groups by an additional precipitation reaction, and confirming the identity of the ion by a reaction test that gives a specific precipitate or color. Several protocols exist for doing this, with cations (positively charged ions) and with anions (negatively charged ions).

Quantitative AnalysisQuantitative analysis is the determination of the amount by weight of each element or compound present in a particular sample of substance. The procedures by which this is achieved include testing for the chemical reaction of a presumed constituent with a reagent or for some well-defined physical property of the putative constituent. Classical methods include use of the analytical balance, gas manometer, burette, and visual inspection of color change. Gas and paper chromatography are important modern methods. Physical techniques such as use of the mass spectrometer and titration are also employed.

Titration:The most common way of doing quantitative analysis is by doing Titration. In this we can determine how much of a solution is needed to fully use up another solution and to complete the reaction. In titration, the atomic mass is used to calculate the number of moles of a substance required using the chemical formula. If we have the concentration of both the solutions then we can directly calculate the volume but in many cases, the concentration of one of the solutions is unknown. This is why one solution is titrated with another. Titration is usually done with an acid and alkali. The neutralization point (point of reaction completion) can determined using a pH indicator. At this point, the pH becomes 7 and the acid and alkali neutralize each other to become salt and water.

In titration, a known volume of one solution (Ex. Acid) is taken using a pipette and placed into a conical flask below the burette. Then a known volume of the other solution (Ex. Alkali) is poured into the burette. Then the valve is slowly opened and drop by drop, the alkali is decanted into the acid in the conical flask. Using the indicator as a guide, the neutralization point can be discerned at the point of colour change at pH 7. The volume of the alkali added is read of the burette. Using these known volumes, the concentration of the known solution and the molar ratio (found from chemical equation), the unknown concentration of the other solution can be calculated.

Chromatography:Column chromatography uses a wide range of adsorbent solids, including alumina and silica gels. Liquids may also be adsorbed on these solids and in turn serve as adsorbents—a process called partition chromatography—which enables chemists to construct columns with very different properties for particular tasks. High performance liquid chromatography, a variant of this technique that is now in common use, employs liquids adsorbed on extremely small and uniform particles to provide very high sensitivity. A pump is required to drive a mixture through the column. Thin-layer chromatography is another form of column chromatography in which the adsorbent material is on a glass or plastic film.

In paper chromatography, a liquid sample flows down a vertical strip of adsorbent paper, on which the components are deposited in specific locations. Another technique, known as gas-liquid chromatography (gas-solid chromatography is a more rarely used variant), permits separation of mixtures of gas compounds or substances that can be vaporized by heat. The vaporized mixture is forced by an inert gas along a narrow, coiled tube packed with a material through which the components flow at different rates and are detected at the end of the tube.

Spectrometer:Spectroscopy, or the study of the interactions of electromagnetic radiation with matter, is the largest and most nearly accurate class of instrumental methods used in chemical analysis and indeed in all of chemistry. The electromagnetic radiation (emr) spectrum is divided into the following wavelength regions: x ray, ultraviolet, visible, infrared, microwave, and radiowave. Emr interactions with matter involve absorption or emission of emr energy by means of transitions between quantized, or discrete, levels of energy for electrons, bond vibrations, molecular rotations, and electron and nuclear spins in atoms and molecules.

Uses of Chemical AnalysisChromatography:Research for analyzing complex mixturesPurifying chemical compoundsDeveloping processes for synthesizing chemical compoundsIsolating natural productsPredicting physical properties of compoundsQuality control to ensure product purityEvaluations of product stabilityAnalyzing air and water for pollutantsMonitoring pesticide levels in the environmentMonitoring food and drug productsAnalyze confiscated narcoticsTesting urine samples in big sporting events for any signs of drugsTitration:Titrations in food and petrochemical industry used to define oils, fats, bio-diesel and similar substances.

Waste water treatmentPaper manufactureColloid scienceWater (moisture) AnalysisDetermination of ionic surfactants in cosmetic productsChemical disinfectants and antiseptics. Quantitative suspension test for the evaluation of bactericidal activity of chemical disinfectants for instruments used in the medical area.

Determination of thrombin and prothrombin concentrations in the blood to keep them at the optimum level.

Spectrometry:Astronomy: to measure the chemical composition and physical properties of astronomical objects or to measure their velocities from the Doppler shift of spectral lines.

To study vibrational, rotational, and other low-frequency modes in a system.

Confocal microscopyFluorescence resonance energy transferFluorescence lifetime imagingX-ray absorption and emission spectroscopy is used in chemistry and material sciences to determine elemental composition and chemical bonding.

Issues related to Chemical AnalysisEconomical:Most of the times, apparatus to conduct proper chemical analysis is very expensive. This is why only a small percentage of the population is actually able to use all the apparatus.

Social:It can be used to identify the ingredients of food products so that the people come to know whether what they are eating is safe or not.

Cultural:Sometimes, chemical analysis helps people to follow their cultures. For example, through chemical analysis, we can find out the ingredients of a food substance. If for example the food substance has beef flavouring, then the Indians will not eat the food.

Environmental:Waste materials which are released into the environment by factories have to be analysed to find out weather they are harmful to the environment or not.

Ethical:Sometimes poisonous substances are added to food flavouring or dyes. Through chemical analysis, the substance can be found out and the company responsible for it can be sued. Chemical Analysis can also detect impurities in drugs. It can find out weather a different impure drug has been added to decrease the cost of the food item. Ex. Recently chemical analysis proved that a local food tofu had been preserved in formaldehyde, and extremely poisonous substance.

ConclusionI conclude that chemical analysis plays a very important role in our daily lives. Without us even realizing it, the technology to conduct chemical analysis is being applied everywhere. It is now becoming more and more widely used all over the world. Indeed it has become so common that the thought of a world without the technology to conduct chemical analysis is terrifying.

Bibliography

Book:Harwood, Richard (2004). IGCSE Chemistry. (Fourth Edition): Cambridge University Press.

Websites:http://en.wikipedia.org/wiki/Qualitative_Analysishttp://wulfenite.fandm.edu/labtech/qualanal.htmhttp://en.wikipedia.org/wiki/Titrationhttp://www.metrohm.com/applications/titration/potentiometric-titration.htmlEncyclopedia:Microsoft Encarta Encyclopedia 2004 Deluxe. Article: Chemical Analysis