heat of combustion


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heat of combustion,

heatheat,
nonmechanical energy in transit, associated with differences in temperature between a system and its surroundings or between parts of the same system. Measures of Heat
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 released during combustioncombustion,
rapid chemical reaction of two or more substances with a characteristic liberation of heat and light; it is commonly called burning. The burning of a fuel (e.g., wood, coal, oil, or natural gas) in air is a familiar example of combustion.
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. In particular, it is the amount of heat released when a given amount (usually 1 molemole,
in chemistry, a quantity of particles of any type equal to Avogadro's number, or 6.02×1023 particles. One gram-molecular weight of any molecular substance contains exactly one mole of molecules.
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) of a combustible pure substance is burned to form incombustible products (e.g., water and carbon dioxide); this amount of heat is a characteristic of the substance. Heats of combustion are used as a basis for comparing the heating value of fuels, since the fuel that produces the greater amount of heat for a given cost is the more economic. Heats of combustion are also used in comparing the stabilities of chemical compounds. For example, if equal quantities of two isomeric hydrocarbons burn to produce equal amounts of carbon dioxide and water, the one releasing more energy (i.e., with the higher heat of combustion) is the less stable, since it was the more energetic in its compounded form.

heat of combustion

[′hēt əv kəm′bəs·chən]
(physical chemistry)
The amount of heat released in the oxidation of 1 mole of a substance at constant pressure, or constant volume. Also known as heat value; heating value.
References in periodicals archive ?
(10) The influence of polyester material modified with inorganic oxides (Mo[O.sub.3] and [SB.sub.2][O.sub.3]) can be also noticed, when analyzing the values of total heat released (THR) and mean effective heat of combustion (HOC), taking into account the mass loss rate of polyesters during combustion.
CFPP ([degrees]C) = 3.1417 x LCSF - 16.477 Oil LCSF ([degrees]C) CFPP ([degrees]C) HVO 1.881 -10.567 CVO 3.173 -9.503 TVO 3.378 -5.864 CSVO 2.219 -9.506 Table 8: The Heat of Combustion (KJ/kg) and the Absolute viscosity Inn Heat of Combustion = 47, 465--[4.187(IV) + 38.31(SV)] KJ/kg Viscosity ln = - 4.7965 + 2525.92962(1/T) + 1.6144 [(SV)2/[T.sup.2]] - 101.06 x [10.sup.-7] [(IV).sup.2] Oil H (KJ/kg) ln HVO 39539.54 96.01 CVO 39197.15 94.76 TVO 39759.41 93.96 CSVO 39964.85 91.99 Where IV = Iodine value SV = Saponification value Table 9: Heating values for neat oils (KJ/kg) and (MJ/kg) Oil HHV (KJ/kg) HHV (MJ/kg) LHV (KJ/kg) LHV (MJ/kg) TVO 39620 39.6 36718 36.7 HVO 40724 40.7 39387 39.4 CSVO 39843 39.8 38147 38.1 CVO 41778 41.8 38672 38.7
Gross heat of combustion of five hardwood species at differing moisture contents.
Theoretical calculation of heat of formation and heat of combustion for several flammable gases.
The heat of combustion of CO to carbon dioxide (CO) is three times greater than the heat of combustion of C to CO, so this represents a large potential energy source for the EAF.
where, [h.sub.R] is the heat of combustion of coke per unit mass.
The most common calorimeter is the bomb calorimeter, which determines the heat of combustion or calorific values of materials in a constant-volume container-a bomb.
The purpose here is to assess the relative roles played by weather (fuel moisture content and wind speed) and fuel (fuel loads, fuel depth, mass density, heat of combustion and surface-area-to-volume ratio) in forest fire behavior.
Part 1 of ISO 5660 describes the measurement of heat release rate, time to ignition, mass loss rate, and effective heat of combustion. Part 2, now in preparation, will contain specifications for measuring smoke obscuration at the same time that the other measurements are being taken.
The data developed were analyzed by several different techniques: Time to Ignition, Maximum Heat Release Rate, Maximum Heat Release Rate per Gram of Sample, Average Heat of Combustion, and Instantaneous Heat Release Rates.
The unit also measures smoke emission, soot mass, toxic gases, ignitability, heat of combustion and mass-loss rate.