One indicates an exothermic reaction. Phase Transitions: Enthalpy changes are associated with phase transitions like melting, vaporization, and sublimation. The change in Enthalpy can be shown as ...

The energy is then released into the surroundings. The change in enthalpy (ΔH) is negative because the energy is being lost by the system (the heater) and gained by the surroundings. Understanding the ...

When the humidity of air changes without a change in enthalpy (total heat content, sensible + latent) the temperature of the air also changes. As a result, this is called an adiabatic process.

Hess’s Law states that the enthalpy change for a chemical reaction is independent of the route taken. This means that the enthalpy change for the overall process will be identical regardless of ...

We can use these bond enthalpies to approximately calculate the enthalpy change for a given reaction.

The fuel cell thermodynamic efficiency is given by the ratio of the Gibbs function change to the Enthalpy change in the overall cell reaction. The Gibbs function change measures the electrical work ...