Tag: Physical Chemistry

The law was revealed by Swiss-Russian chemist and doctor Germain Henri Hess. He introduced the law in its 1840’s publication.

The four laws are the zeroth law, the first law, the second law, and the third law. These laws are universally valid to any thermodynamic system and are described as follows:

Different types of chemical reactions.

In chemistry, our concern is not with the absolute value of enthalpy but rather the change in the enthalpy. The absolute enthalpy cannot be estimated directly since the value of the absolute internal energy cannot be reckoned for real systems. Further, in chemistry and thermodynamics, we are interested in measuring the change in enthalpy, not its absolute value.