Calculate the number of atoms present in 1.625 g metal if it forms bcc unit cell structure.
$[ \rho \times a^3 = 3.25 \times 10^{-22}\ \text{g}]$

Identify the covalent crystal from the following.

If a 0.4 molal solution of a nonvolatile solute in organic solvent decreases its freezing point by 2.4 K., then the molal depression constant of solvent will be

Which of the following colligative properties is useful to determine the molar masses of proteins, polymers or colloids, with the greatest precision?