Solid State — Prelims Questions

An element crystallizes in a face-centred cubic (FCC) lattice. If the edge length of the unit cell is $400 \text{ pm}$ and the density of the element is $10 \text{ g/cm}^3$, what is the approximate atomic mass of the element? (Given: Avogadro's number $N_A = 6.022 \times 10^{23} \text{ mol}^{-1}$)

Which of the following statements is INCORRECT regarding point defects in ionic solids?

A metal crystallizes with a body-centred cubic (BCC) lattice. The edge length of the unit cell is $300 \text{ pm}$. What is the radius of the atom?

Which of the following statements correctly describes the magnetic properties of a substance?

In a solid, oxide ions (O$^{2-}$) are arranged in a cubic close-packed (CCP) structure, while cations A$^{3+}$ occupy one-sixth of the tetrahedral voids and cations B$^{2+}$ occupy one-third of the octahedral voids. What is the formula of the compound?

Which of the following is an example of a covalent (network) solid?