Question

What is the difference between enthalpy of formation, combustion, solution, and neutralization?

Answer 1

A thermodynamic system's enthalpy is defined as the sum of the system's internal energy and the product of its pressure and volume. It is a state function that is employed in many chemical, biological, and physical tests under constant pressure, which is easily given by the vast ambient environment. The effort necessary to create the system's physical dimensions, i.e. to make space for it by displacing its surrounds, is expressed by the pressure–volume term. Enthalpy depends simply on the ultimate configuration of internal energy, pressure, and volume as a state function, not on the journey taken to get there.

Complete answer:
Because the internal energy of a system comprises components that are unknown, difficult to access, or not of interest in thermodynamics, the total enthalpy of a system cannot be measured directly. In practise, because it simplifies the explanation of energy transfer, a change in enthalpy is the preferred phrase for observations at constant pressure. At constant pressure, the enthalpy change equals the energy exchanged with the environment via heat when matter transport into or out of the system is likewise blocked.
The change in enthalpy that occurs when one mole of a compound is created from its components in their standard states (298 K and 1 bar pressure) is known as the standard heat of formation $\Delta {{H}_{f}}$. The standard heat of creation of all elements is set to zero by convention.
The change in enthalpy of a system when one mole of a material is entirely burned in excess of air or oxygen is defined as heat of combustion. $\Delta {{H}_{C}}$ is the abbreviation for it.
When a material is dissolved in a solvent, heat changes are common. The change in enthalpy when one mole of a material is dissolved in a specific amount of solvent at a certain temperature is known as the heat of solution.
“The change in enthalpy when one gram equivalent of an acid is fully neutralised by one gram equivalent of a base or vice versa in dilute solution,” according to the heat of neutralisation definition.

Note:
The enthalpy of an ideal gas is unaffected by pressure and is solely determined by its temperature, which is proportional to its internal energy. Real gases behave similarly to this behaviour at typical temperatures and pressures, making thermodynamic design and analysis easier.