Distillation in Modern Chemistry Laboratory

In simple terminology, distillation is defined as the method of purifying a liquid by boiling it and condensing its vapors. In other words, any liquid when it is heated and becomes fully boiled, the process of distillation captures and cools the resultant hot vapors, and collect the condensed vapors. This method or process is not a chemical reaction but a unit operation or physical separation. In a modern chemistry laboratory, distillation is a very important requirement to identify and purify the organic compounds.

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Boiling Point Determination
The chemistry teaching labs make use of distillation regularly, for two purpose: identification of organic compounds and the purification of organic compounds.
The boiling point of a compound implies the physical features or properties of a compound by which it is distinguished. In a laboratory, distillation is used to purify a compound. This is done by separating the compound from less-volatile or a non-volatile material. There are different compounds in different points in a mixture and the individual components are separated, when there is a careful distillation of the mixture.
This point is actually the temperature at which there is an equality of vapor pressure of the liquid phase of a compound to the external pressure working on the liquid's surface. This outside pressure is usually the atmospheric pressure. The liquid is heated. The vapor pressure of the liquid will increase where there is an increase in the temperature of the liquid. The liquid will boil when the vapor pressure is equal to the atmospheric pressure. It is known that different compounds boil at different temperatures because each compound has its own vapor pressure. It is to be noted that compounds with higher vapor pressures will boil at lower temperatures.
The distillation process of determining a boiling point measures the temperature of the vapors above the liquid and these vapors are the same temperature as the boiling liquid. If the boiling point is used to find a solid compound, it is necessary to compare this with that of the true compound.
Compound Purification Distillation
Simple Distillation: In chemistry laboratory, simple distillation is used. Fractional Distillation: When the boiling points are similar, mixtures of liquids cannot be separated by a single simple distillation. In such cases, fractional distillation is used. It is used to separate the components by vaporization-condensation cycles within a fractionating column and this is repeatedly done.
Vacuum Distillation:This distillation is done at a reduced pressure. In this process, the compound need not be heated to very high temperature for it to boil. This is because, the boiling point of a compound is lower at a lower external pressure. This distillation process is used to distill compounds that have a high point.

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Basic Chemistry Lab Safety

The world of science, especially chemistry can be absolutely loads of fun to explore and learn about. Learning about what different materials are made of and how these materials react or interact with other materials is a field of study that dates back literally thousands of years. Even ancient civilizations, as far back as ancient Greece had individuals within their societies that practiced and ancient form of this branch of science.

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But regardless of what time period an individual practicing chemistry may have lived in the hazards of working with chemicals have always been present. For this reason, basic lab safety equipment is required when working with chemicals of any nature. Eye Protection. Your eyes are very delicate instruments. When working with chemicals of any nature, your eyes must always be protected. Regardless of the type of chemical you are working with, the potential for solids such as salts or liquids such as solvents can easily splash. For this reason, safety goggles are recommended at all times. Goggles reduce the probability of chemicals that may burn or scratch your eye from getting in your eyes.

Skin Protection. As with the case of your eyes, the protection of your skin is also important. Just as in the case of your eyes, your skin can easily be damaged by many common chemicals, even common ones found in the household. For this reason, your skin must be protected at all times. Two items that will assist in protecting your skin are a lab coat and gloves. A lab coat is necessary so as to provide a protective barrier between the chemical being handled and your skin.

Certain chemicals, depending on the type, can burn your skin and leave permanent marks or worse. Your lab coat should always be clean. Never wear a lab coat that has chemicals on it. Additionally, gloves designed for use with chemicals will help protect the skin on your hands from being affected by the chemicals you are working with. One note of caution. Not all gloves protect from all chemicals. To find out what gloves are to be used for any certain chemical, check the required Personal Protective Equipment (PPE) as found on that chemical's Manufacturer Safety Data Sheet (MSDS). Respiratory Protection. Just as important as your eyes and skin are your lungs.

Chemical vapors can easily and almost instantly enter your bloodstream through your respiratory system. Two of the main things that are required to help prevent this from happening are a chemical respirator and a well-ventilated work area. A chemical respirator reduces the amount of vapors that are present in the air you are breathing in. However, a chemical respirator should not be your first line of respiratory defense against vapors. Your first and primary method of protection should be from mechanical ventilation. Mechanical ventilation removes the vapors and takes them away from the work area. Practicing chemistry can be a lot of fun, if it is practiced safely. Reading this article does NOT qualify you to work with chemicals. Do not handle chemicals unless you have been trained by appropriately authorized and qualified personnel.

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