13 past paper MCQs on Lattice Energy, from the Solids unit of MDCAT Chemistry. The year each question appeared is shown where known; tap “Show answer” for the correct option and a short solution.
1.All of the following steps are used to calculate the lattice energy in the Born-Haber cycle EXCEPT: (MDCAT 2024)
Correct answer: (c) deionizing the metal
The cycle atomizes and ionizes; there is no step that returns an ion to its atom.
2.The factor that affects the lattice energy is: (NUMS MDCAT 2025)
Correct answer: (a) Charge to size ratio
Lattice energy rises with the charge on the ions and falls with their size.
3.The ionic compound among the following with the highest lattice energy is: (SIBA MDCAT 2025)
Correct answer: (a) LiF
Lattice energy is greatest for the smallest ions, and lithium fluoride has the smallest pair here.
4.Which of the following compound has lower Lattice Energy? (SZABMU MDCAT 2025)
Correct answer: (b) KCl
Lattice energy falls as the ions get bigger, and the potassium ion is the largest of the singly charged ones here.
5.All of the following steps are used to calculate the lattice energy in Born-Haber cycle EXCEPT (UHS MDCAT 2024)
Correct answer: (c) Delonlize the metal
The Born-Haber cycle atomizes and ionizes the metal and adds electrons to the non-metal; nothing is de-ionized.
6.The heat of sublimation of potassium is 98kJ/mol, the heat of dissociation of bromine gas is 192.5 kJ/mol. The ionization energy of K is 414 kJ/mol. The electron affinity of Br is -334.7 kJ/mol and the heat of formation of KBr is -405.8 kJ/mol. Calculate the lattice energy of KBr. (KMU MDCAT 2024)
Correct answer: (a) -679.3
The cycle gives $-405.8-(98+96.25+414-334.7)$, that is $-679.3\,\mathrm{kJ\,mol^{-1}}$.
7.The greater Lattice energy is shown by: (NUMS MDCAT 2023)
Correct answer: (d) NaF
Lattice energy is greatest for the smallest ions, and fluoride is the smallest halide.
8.Equation represents which energy change? Mg2+(g) + O2−(g) → MgO(s) (NUMS MDCAT 2023)
Correct answer: (c) Lattice energy
Gaseous ions coming together into one mole of the solid release the lattice energy.
9.Born Haber cycle is used to determine: (PMC MDCAT 2022)
Correct answer: (a) Enthalpy of lattice
The Born-Haber cycle gives the lattice energy, which cannot be measured directly.
10.What is the value of lattice energy when one mole of an ionic crystal is formed? (PMC MDCAT 2022)
Correct answer: (b) Negative value
Energy is released when the gaseous ions come together, so the lattice energy is negative.
11.Lattice energy does not depend on the: (PMC MDCAT 2022)
Correct answer: (d) Room temperature
Lattice energy turns on the charges and sizes of the ions; the temperature of the room does not enter.
12.The Lattice energy is also called as: (PMC MDCAT 2020)
Correct answer: (c) Crystal energy
Lattice energy is also called crystal energy.
13.Born-Haber cycle is used to determine the lattice energies of: (PMC MDCAT 2020)
Correct answer: (c) Ionic solids
The Born-Haber cycle gives the lattice energy of an ionic crystal, which cannot be measured directly.