Fractional distillation
Overview
 
Fractional distillation is the separation of a mixture
Mixture
In chemistry, a mixture is a material system made up by two or more different substances which are mixed together but are not combined chemically...

 into its component parts, or fractions, such as in separating chemical compound
Chemical compound
A chemical compound is a pure chemical substance consisting of two or more different chemical elements that can be separated into simpler substances by chemical reactions. Chemical compounds have a unique and defined chemical structure; they consist of a fixed ratio of atoms that are held together...

s by their boiling point
Boiling point
The boiling point of an element or a substance is the temperature at which the vapor pressure of the liquid equals the environmental pressure surrounding the liquid....

 by heating them to a temperature
Temperature
Temperature is a physical property of matter that quantitatively expresses the common notions of hot and cold. Objects of low temperature are cold, while various degrees of higher temperatures are referred to as warm or hot...

 at which several fractions of the compound will evaporate. It is a special type of distillation
Distillation
Distillation is a method of separating mixtures based on differences in volatilities of components in a boiling liquid mixture. Distillation is a unit operation, or a physical separation process, and not a chemical reaction....

. Generally the component parts boil at less than 25 °C from each other under a pressure of one atmosphere
Atmosphere
An atmosphere is a layer of gases that may surround a material body of sufficient mass, and that is held in place by the gravity of the body. An atmosphere may be retained for a longer duration, if the gravity is high and the atmosphere's temperature is low...

 (atm
Atmosphere (unit)
The standard atmosphere is an international reference pressure defined as 101325 Pa and formerly used as unit of pressure. For practical purposes it has been replaced by the bar which is 105 Pa...

). If the difference in boiling points
Boiling Points
Boiling Points is a prank reality television show, much like the format used on Candid Camera. It is broadcast on MTV in the United States. In each half-hour episode, annoying situations are set up and deliberately inflicted on one or more young adults who are unaware that they are being tested...

 is greater than 25 °C, a simple distillation is used.
Fractional distillation in a laboratory makes use of common laboratory glassware and apparatuses, typically including a Bunsen burner
Bunsen burner
A Bunsen burner, named after Robert Bunsen, is a common piece of laboratory equipment that produces a single open gas flame, which is used for heating, sterilization, and combustion.- Operation:...

, a round-bottomed flask and a condenser
Condenser (heat transfer)
In systems involving heat transfer, a condenser is a device or unit used to condense a substance from its gaseous to its liquid state, typically by cooling it. In so doing, the latent heat is given up by the substance, and will transfer to the condenser coolant...

, as well as the single-purpose fractionating column
Fractionating column
A fractionating column or fractionation column is an essential item used in the distillation of liquid mixtures so as to separate the mixture into its component parts, or fractions, based on the differences in their volatilities...

.
  • heat source, such as a hot plate
    Hot plate
    A hot plate is a portable self-contained tabletop small appliance that features one, two or more gas burners or electric heating elements. A hot plate can be used as a stand alone appliance, but is often used as a substitute for one of the burners from an oven range or the cook top of a stove...

     with a bath, and ideally with a magnetic stirrer.
  • distilling flask, typically a round-bottom flask
    Round-bottom flask
    Round-bottom flasks are types of flasks having spherical bottoms used as laboratory glassware, mostly for chemical or biochemical work. They are typically made of glass for chemical inertness; and in modern days, they are usually made of heat-resistant borosilicate glass...

  • receiving flask, often also a round-bottom flask
  • fractionating column
    Fractionating column
    A fractionating column or fractionation column is an essential item used in the distillation of liquid mixtures so as to separate the mixture into its component parts, or fractions, based on the differences in their volatilities...

  • distillation head
  • thermometer
    Thermometer
    Developed during the 16th and 17th centuries, a thermometer is a device that measures temperature or temperature gradient using a variety of different principles. A thermometer has two important elements: the temperature sensor Developed during the 16th and 17th centuries, a thermometer (from the...

     and adapter if needed
  • condenser
    Condenser (heat transfer)
    In systems involving heat transfer, a condenser is a device or unit used to condense a substance from its gaseous to its liquid state, typically by cooling it. In so doing, the latent heat is given up by the substance, and will transfer to the condenser coolant...

    , such as a Liebig condenser, Graham condenser or Allihn condenser
  • vacuum adapter (not used in image to the right)
  • boiling chip
    Boiling chip
    A boiling chip or boiling stone is a small, irregularly shaped piece of material added to liquids to make them boil more smoothly. Boiling chips are frequently employed in distillation and heating. When a liquid becomes superheated, a particle of dust or a stirring rod can cause flash boiling...

    s, also known as anti-bumping granules
  • Standard laboratory glassware
    Laboratory glassware
    Laboratory glassware refers to a variety of equipment, traditionally made of glass, used for scientific experiments and other work in science, especially in chemistry and biology laboratories...

     with ground glass joint
    Ground glass joint
    Ground glass joints are used in laboratories to quickly and easily fit leak-tight apparatus together from commonly available parts. For example, a round bottom flask, Liebig condenser, and oil bubbler with ground glass joints may be rapidly fitted together to reflux a reaction mixture...

    s, e.g.
 
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