/kal'euh rim"i teuhr/, n.
an apparatus for measuring quantities of heat.
[1785-95; CALORI- + -METER]

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Device for measuring heat produced during a mechanical, electrical, or chemical reaction and for calculating the heat capacity of materials.

A common design, known as a bomb calorimeter, consists of a reaction chamber surrounded by a liquid that absorbs the heat produced by the reaction. The amount of heat can be determined from the increase in temperature, taking into account the properties of the container and the liquid.

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      device for measuring the heat developed during a mechanical, electrical, or chemical reaction, and for calculating the heat capacity of materials.

      Calorimeters have been designed in great variety. One type in widespread use, called a bomb calorimeter, basically consists of an enclosure in which the reaction takes place, surrounded by a liquid, such as water, that absorbs the heat of the reaction and thus increases in temperature. Measurement of this temperature rise and a knowledge of the weight and heat characteristics of the container and liquid permits the total amount of heat generated to be calculated.

 The design of a typical bomb calorimeter is shown in the Figure—>. The material to be analyzed is deposited inside a steel reaction vessel called a bomb. The steel bomb is placed inside a bucket filled with water, which is kept at a constant temperature relative to the entire calorimeter by use of a heater and a stirrer. The temperature of the water is monitored with a thermometer fitted with a magnifying eyepiece, which allows accurate readings to be taken. Heat losses are minimized by inserting an air space between the bucket and an exterior insulating jacket. Slots at the top of the steel bomb allow ignition wires and an oxygen supply to enter the vessel, both of which are critical in starting the chemical reaction. When an electric current passes through the ignition coil, a combustion reaction occurs. The heat released from the sample is largely absorbed by the water, which results in an increase in temperature. Bomb calorimeters have been developed to the point that heats of combustion of organic materials can be measured with results reproducible within 0.01 percent.

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Universalium. 2010.

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Look at other dictionaries:

  • Calorimeter — Cal o*rim e*ter, n. [L. calor heat + meter; cf. F. calorim[ e]tre.] 1. (Physiol.) An apparatus for measuring the amount of heat contained in bodies or developed by some mechanical or chemical process, as friction, chemical combination, combustion …   The Collaborative International Dictionary of English

  • Calorimeter — (v. lat. u. gr.), 1) so v.w. Thermometer; 2) ein von Rumford erfundenes Instrument zur Bestimmung der durch Verbrennung entstehenden Wärmemenge, indem man hierbei untersucht, um wie viel Grade eine bestimmte Quantität Wasser erwärmt wird. Es ist… …   Pierer's Universal-Lexikon

  • Calorimeter — Calorimeter, s. Wärmemesser …   Herders Conversations-Lexikon

  • calorimeter — 1794, from CALORIE (Cf. calorie) + METER (Cf. meter). A hybrid word …   Etymology dictionary

  • calorimeter — ► NOUN ▪ an apparatus for measuring the amount of heat involved in a chemical reaction or other process. DERIVATIVES calorimetric adjective calorimetry noun …   English terms dictionary

  • calorimeter — [kal΄ə rim′ət ər] n. [< L calor (see CALORIFIC) + METER] an apparatus for measuring amounts of heat, as in chemical combination, friction, etc …   English World dictionary

  • Calorimeter — This article is about heat measuring devices. For particle detectors, see Calorimeter (particle physics). The world’s first ice calorimeter, used in the winter of 1782 83, by Antoine Lavoisier and Pierre Simon Laplace, to determine the heat… …   Wikipedia

  • calorimeter — n as used in Test Method D5865, the bomb and its contents, the calorimeter vessel with stirrer, the water in which the bomb is immersed, and the portions of the thermometer and the ignition leads within the calorimeter vessel. D5865 …   Coke&Coal Terminology

  • calorimeter — An apparatus for measuring the amount of heat liberated in a chemical reaction. [L. calor, heat, + G. metron, measure] Benedict Roth c. Benedict Roth apparatus. bomb c. an instrument for determining the potential energy …   Medical dictionary

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