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NEETChemistryThermodynamics (C)

What is the standard enthalpy of combustion defined as?

Options

  1. AThe enthalpy change when a substance undergoes combustion in any state
  2. BThe enthalpy change when a substance undergoes combustion in its standard state at any temperature
  3. CThe enthalpy change when a substance undergoes combustion in its standard state at a specified temperature
  4. DThe enthalpy change when a substance undergoes combustion in its gaseous state

Correct answer

C. The enthalpy change when a substance undergoes combustion in its standard state at a specified temperature

Step-by-step solution

The standard enthalpy of combustion is defined as the enthalpy change per mole (or per unit amount) of a substance when it undergoes combustion, with all the reactants and products being in their standard states at a specified temperature.

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