Which of the following analytical techniques and statements accurately apply to the determination of — Mole Concept and Some Basic Concepts of Chemistry Chemistry Question
Question
Which of the following analytical techniques and statements accurately apply to the determination of molecular and atomic masses?
💡 Solution & Explanation
Statement A is false; atoms are far too light ($\approx 10^{-23}\text{ g}$) to be weighed on macroscopic analytical balances; they require mass spectrometers. Statement B is true; mass spec separates isotopes by mass-to-charge ratio. Statement C is true; ionic compounds form continuous 3D crystal lattices (like $NaCl$), so we calculate the mass of their empirical "formula unit" rather than a discrete "molecule". Statement D is false; $1\text{ u}$ is $1.66056 \times 10^{-24}$ *grams*, which equals $1.66056 \times 10^{-27}$ *kilograms*.