The heat of combustion of a fuel (A) Is equal to the heat of formation (B) Is always negative (C) Can’t be known without calculating it (D) Is always positiveThe heat of combustion of a fuel(A) Is equal to the heat of formation(B) Is always negative(C) Can’t be known without calculating it(D) Is always positive

The heat of combustion of a fuel
(A) Is equal to the heat of formation
(B) Is always negative
(C) Can’t be known without calculating it
(D) Is always positive
by

1 Answer

Answer :

(B) Is always negative
by

Related questions

Pick out the wrong statement. (A) Theoretical flame temperature is the temperature attained by the products of combustion, when the fuel is burned without loss or gain of heat (B) Burning the fuel with theoretically required amount of pure oxygen results in attainment of maximum adiabatic flame temperature (C) Burning the fuel with excess pure oxygen results in maximum theoretical flame temperature (D) Adiabatic flame temperatures of actual combustions are always less than the maximum values

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In practical operation of any furnace, zero oxygen percentage or theoretical CO2 percentage in flue gas is rarely achieved, because of (A) Use of non-preheated combustion air (B) Use of pulverised solid fuels (C) Imperfect mixing of fuel & air and infiltration of air (D) Use of excessive positive draft in the furnace

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