Bunsen burner
The Bunsen burner is a small gas burner in which the fuel gas, the combustion air partially draws on the principle of a jet pump itself.
The Bunsen burner is often used in addition to the Teclu in chemical laboratories for heating of fabric samples or liquids. The Bunsen burner is named after Robert Wilhelm Bunsen (1811-1899); However, the original invention is by Michael Faraday and was designed by Peter Desaga, the lab assistant Bunsen, in 1855 improved significantly in Heidelberg.
Design and operation
The laboratory gas burner consists of an approximately 15 cm long piece of pipe, in which the gas flows upward while sucking through adjustable openings on the principle of a jet pump, the combustion air itself. Through a grid or fine holes on the upper end of the burner, a check of the flame in the burner is prevented in modern burners. The burner is generally operated with propane, butane or Stadt-/Erdgas.
The burner stands on a heavy foot on which the fuel gas supply is attached. Perpendicular to a tube is arranged like a small vent. The fuel gas passes through the supply to an opening passing through an oxidant, usually air, is sucked. The opening is adjustable in width. At the upper end of the tube, the gas is ignited and burned. With open air supply to the oxidizer and fuel gas mix already within the Bunsen burner. The flame then burns as blue and hot premixed flame. If the port is closed, the fuel gas is mixed with the oxidizer until the upper tube output and developed lower temperature. Such a diffusion flame, also known as luminous flame is cooler up to 900 ° C and turns yellow. Intermediate forms of the flame are called Teilvormischflammen. The flame heat can be between 350 and about 1000 ° C ( 1300 ° Teclu C) can be regulated. The flame is divided into core, mantle, and the almost invisible flame edge. In essence, there is a temperature of about 250-550 ° C, jacket ( depending on the source between 1000 ° C and 1200 ° C) and hem ( about 900 ° C), however, are significantly hotter, but less well to recognize, since the gas almost completely burned. The is forming in a premixed flame and to a lesser extent at a Teilvormischflamme cones after oxidizing flame ( outside) distinguished and reducing flame (inside), which show the greatest temperature at the transition.
By the Bunsen burner flame two different types are distinguished, the diffusion flame, the premixed flame
Application
Application, see Bunsen burner especially in preliminary tests of analytical chemistry, for example, the Lötrohrprobe, the borax or phosphorus pearl and the flame color. Also can be provided with a fully open air that creates a sterile environment around the flame. Thus, it is possible to carry out sterile operations in the vicinity of the flame, such as in the microbiology. Also in the molecular cuisine Bunsen burner used for heating different foods.