The calorific value of a fuel is expressed in _______.

kilojoule per kilogram

The calorific value of a fuel is expressed in kilojoules per kilogram (kJ/kg). It represents the amount of heat energy released when a unit mass of the fuel undergoes complete combustion under standard conditions.

Concept Explanation:

The calorific value is a critical measure used to evaluate the energy efficiency of a fuel. It indicates how much energy can be extracted from a given quantity of the fuel. Fuels with higher calorific values release more energy, making them more efficient and desirable for use in industries, transportation, and domestic purposes.

The calorific value is determined under controlled conditions and can be categorized into two types:

1. Gross Calorific Value (GCV): Includes the total energy released during combustion, accounting for the latent heat of water vapor.
2. Net Calorific Value (NCV): Excludes the energy lost as latent heat of water vapor.

Why is it Expressed in kJ/kg?

The unit kilojoules per kilogram (kJ/kg) provides a standardized way to measure and compare the energy content of various fuels. It ensures consistency across industries and simplifies calculations involving energy efficiency.