Question

Born -Haber cycle may be used
(A) to find out electron affinity of non-metal atoms
(B) to find out lattice energy of the ionic compounds
(C) for the preparation of ammonia in industries
(D) both A and B

Answer 1

The Born–Haber cycle is an approach to analyze the energy of a given reaction. It was named after two German scientists Max Born and Fritz Haber, who developed it in 1919.

Complete step by step solution:
The first question that comes to our mind is what is the Born-Haber cycle?
Born-Haber cycle is a cycle of enthalpy change of process that leads to the formation of a solid crystalline ionic compound from the elemental atoms in their standard state and of the enthalpy of formation of the solid compound such that the net enthalpy of the reaction becomes zero.
Born–Haber cycles are used primarily as a means of calculating lattice energy, which cannot otherwise be measured directly. The lattice energy is the enthalpy change involved in the formation of an ionic compound from gaseous ions, or sometimes defined as the energy to break the ionic compound into gaseous ions. A Born–Haber cycle applies Hess's law (The change of enthalpy in a chemical reaction is independent of the pathway between the initial and final states.) to calculate the lattice enthalpy by comparing the standard enthalpy change of formation of the ionic compound (from the elements) to the enthalpy required to make gaseous ions from the elements.
To make gaseous ions from elements it is necessary to turn each element into gaseous atoms and then to ionize the atoms. If the element is normally a molecule then we first have to consider its bond dissociation enthalpy. The energy required to remove one or more electrons to make a cation is a sum of successive ionization energies. The amount of energy released when an electron is added to a neutral atom or molecule in the gaseous state to form a negative ion is known as electron affinity.
From the above discussion, it is clear that both (A) and (B) are correct.

Hence, the correct answer is option (D).

Note: Always remember that in the Born-Haber cycle, the word cycle refers to the fact that one can also equate to zero the total enthalpy changes for a cyclic process.