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  Home >> Chemistry Dictionary >>Buchner Funel Butanedioic Acid

Buchner funel. A type of funel with an internal perforated tray on which a flat circular filter paper can be placed, used for filtering by suction.

Bumping. The forming of very larger bubbles when a liquid boils. As a bubble rises, the vessel containing the liquid jumps up and down.

Bunsen burner. A burner for coal-gas used in laboratories. It consists of a metal tube with an adjustable air valve for burning a mixture gas and air. IT is named after R.W. Bunsen (1811-99).

Burette. Apparatus used for measuring the quantity of a liquid or gas in a chemical operation. In volumetric analysis the burette generally consists of a vertical tube, graduated in fraction of mililitre, provided with a tap at the lower end, by means of which the amount of liquid which is allowed to flow from the graduated tube may be controlled. In more precise work, a weight burette is employed. It consists of a flat-bottomed flask provided with a ground stopper, and a narrow side limb provided with a ground glass cap. The burrette is weighed before and after releasing the requisite amount of liquid from the narrow sidelimb.
Burettes can be automated for continuous use.

Bunsen burner. A laboratory gas burner having a vertical metal tube into which the gas is led, with a hole in the side of the base of the tube to admit air. The amount of air can be regulated by a sleeve on the tube. When no air is admitted the flame is luminous and smoky. With air, it has a fainty visible hot outer part (the oxidizing part) and an inner blue cone where combustion is incomplete (the cooler reducing part of the flame).

Burning oils. Kerosenes for domestic use.

Butanal, (Butyraldebyde). A colourless flammable liquid aldehyde, C3H9CHO; r.d. 0.8; m.p. - 109°C; b.p. 75.7°C.

Butane. A gaseous hydrocarbon, C4H10; d. 0.58 g. cm-3; m.p - 135°C; b.p. 0°C. Butane is obtained from petroleum (from refinery gas or by cracking higher hydrocarbons). The fourth number of the alkane series, it has a straight chain of carbon atoms and is isomeric with 2-methyl-propane (CH3CH(CH3)CH3, formerly called isobutan). It can easily be liquefied under pressure and is supplied in cylinders for use as fuel gas. It is also a raw material for making buta-1,3-diene (for synthetic rubber).

Butanedioic acid. (succinic acid). A colourless crystalline fatty acid, (CH2)2 (COOH)2; r.d. 1.5; m.p. 185°C b.p. 235°C. A weak carboxylic acid occurring in certain plants, it is produced by fermentation of sugar or ammonium tartrate and used as a sequestrant and in making dyes.

Butanoyl. Groups formed from the butanoic acids by removal of the OH. Thus butanoyl, n-butryl, CH3CH2CH2C(O)—2,-methylpropanoyl, isobutyryl, (CH3)2CHC(O)—.

Butyl group. The organic group CH3 (CH2)3.

By-product. A compound formed during a chemical reaction at the same time as the main product. Commercially useful by products are obtained from a number of industrial processes. For example, calcium chloride is a by-product of the Solvay process for making sodium carbonate. Propanone is a by-products in the manufacture of phenol.

           
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