What is chemistry on the bench?

Bench Chemistry is a type that is performed in the most traditional way-scientific mixtures and processes chemicals directly, not using any of the top devices or theoretical approaches that can be associated with the latest aspects of discipline. Essentially includes experiments and demonstrations that can be performed using several chemicals; Some test tube, flasks and beaker; and Bunsen Burner. The stereotypical image of a scientist in a white laboratory coat pouring chemicals from one tube into another is a perfect example of a bench chemistry. "Wet Chemistry" is sometimes used as a synonym for this activity; However, it is an industrial term with a much more flexible definition and can also refer to the use of high-tech devices that are generally not in the laboratory desk.

techniques

The term "chemistry bench" covers many different scientific techniques used in the laboratory. The general rule is that if they are to get a method that can be easily practiced on a desk, anThe computer would perform most of the calculations and analyzes, then it is a technique of chemistry on the bench. Analytical methods include titration, gravimetric analysis, flame tests and borax beads. Samples of elements or compounds can also be prepared for a desk. Experimenting or simply mixing things together to find out what happens is often a bench, and in this way many important discoveries are carried out in this way.

Analytical methods

A lot of chemistry is about analysis: exploring the sample of the material to determine what elements or compounds contain. Although there are tools such as spectrometers that can be used to perform detailed analyzes, there is also a wide range of direct bench tests that can simply be performed by mixing one or two substances or something heating in the Bunsen flame. These pits can be old -fashioned but do not require expensive equipment and can teach students a lot about chEmiii. In the past, they led to important breakthroughs such as the discovery of new elements.

titration - sometimes called volume analysis - is a method used to determine the concentration of dissolved compound. For example, if a chemist wants to know how much hydrochloric acid is present in a solution in water, an alkaline solution such as sodium hydroxide can add known concentration until the resulting solution is neutral. It is then possible to calculate the concentration of hydrochloric acid from the volume of the sodium hydroxide solution used.

Gravimetric analysis relies on weight rather than volume and includes weighing compounds or interest after its insulation from the sample. For example, in order to determine the amount of metal present in the Ruda, the chemist could first dissolve the ore in acid and then add a buddy that reacts with the metal to form a compound that is not soluble. This comes out of the solution as a fine powder known as a clot, which can then be filtered and considered. Then it is possible to know the atomic weight of the metal and ostaThose elements in a colored compound to determine how much metal was present in Ruda.

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Flame test is based on the colors produced when certain metals are strongly heated in Bunsen's flame. For example, barium gives green, strontium, red and cesium, blue. The test is usually performed using a platinum wire with a small loop at the end, which is used to pick up a small amount of sample and to introduce flame.

Another way to detect metals is the Borax bead test. Again using platinum wire loops, a small amount of borax (sodium tetrabor), it is melted in Bunsen's flame and then used to pick up a small amount of sample. This mixture is then melted in the flame and creates an amy round bead. The metals present in the sample will produce beads of different colors. The color also depends on the part of the flame in which the bead is heated, and the bead can change the color when it cools. From the colors made, it is often possible to determine which metal is present.

Preparing Samples of ChemikÁli

Bench methods can also be used to prepare or clean samples of specific chemicals. Distillation is a common technique. A mixture of liquids with different boiling points - for example water and ethanol - can be separated by placing in the flask connected to the capacitor or in the retress and heating to the temperature above the boiling point, but below the boiling point of the other. The liquid with the lower boiling point is evaporated and can be condensed and collected.

collision is another method that can be used to prepare a chemical that is insoluble in water. Pure calcium carbonate (CACO _{3 ), for example, can be prepared by mixing the soluble calcium soluble solution - such as calcium chloride (CACL ) - with soluble carbonate solution - such as sodium carbonate. Calcium carbonate forms a clot on the bottom of the beaker. The second reaction product, sodium chloride (NaCl), which is soluble, can be obtained by evaporation of the remaining liquid. This method can be usedto prepare many different compounds.}

bench

Bench Chemistry gets its name from a traditional laboratory desk. They are located in industrial and academic laboratories, and almost anyone who learns natural sciences will work on one of these benches at some point. Usually stains, heat and corrosion are resistant to, so chemical leaks and experiments do not cause significant damage and can be equipped with gas sockets to which Bunsen's burner can be connected. Some work tables are also surrounded by ventilation systems known as a hood that protects users from toxic gases that can be released during certain chemical reactions.