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Hess’s Law

Statement of Hess’s Law Hess’s law of constant heat summation states that the total enthalpy change in a particular reaction is constant regardless whether it occurs in one step or more. Explanation of Hess’s Law According to Hess’s law, if A reacts to form the product B, it doesn’t matter how many steps involved to … Read more

Lattice Energy

Lattice Energy Definition Ionic compounds are more stable because of their elctrostatic force between the two opposite ions. After the formation of ions, they combine together to form ionic compound. The energy released in this process is known as lattice energy or lattice enthalpy. That means, energy released when a cation and a anion combine … Read more

Enthalpy Change

Enthalpy Change Definition Enthalpy change is the heat change accompanying a chemical reaction at constant volume or constant pressure. The enthalpy change tells the amount of heat absorbed or evolved during the reaction. It is denoted by ΔH. Types of Enthalpy Change Enthalpy change of a reaction expressed in different ways depending on the nature … Read more