Chemistry
Chemistry
Problem
Two different gas–liquid systems are being considered for capturing hazardous gases in a scrubber column operating at 20 °C and 1 atm. System A: hydrogen chloride gas (HCl, μ = 1.08 D) bubbled through xenon (Xe, α = 4.04 ų) that has been liquefied under modest pressure. System B: hydrogen bromide gas (HBr, μ = 0.79 D) bubbled through liquid carbon tetrachloride (CCl₄, α = 10.0 ų). Assume that, within each system, the dominant attractive forces between the gaseous acid and the liquid medium are dipole-induced dipole attractions and London dispersion forces. (a) Propose a quantitative or semi-quantitative method to compare the dipole-induced dipole attraction strength for System A versus System B using only the numerical data provided. Execute the comparison and state which system is predicted to exhibit the stronger dipole-induced dipole interaction. (b) Discuss how London dispersion forces in each system might compete with—or reinforce—the dipole-induced dipole interactions you analyzed in part (a). In your discussion, consider relative molar masses and electron counts. (c) Taking both types of intermolecular forces into account, predict which system will more effectively absorb its respective gaseous acid under the stated conditions. Justify your conclusion with a coherent argument that references parts (a) and (b).Intuitive explanation
Gas absorption efficiency depends on how strongly the dissolved gas molecules interact with the liquid solvent. Here, you're comparing two systems using their molecular properties—dipole moment () and polarizability ()—to predict which will have stronger intermolecular attractions. The key insight is that dipole-induced dipole interactions scale with , while dispersion forces depend on the liquid's polarizability. By calculating the interaction strength for each gas-liquid pair, you can rank which system will dissolve and capture the hazardous gas more effectively.
Intuitive explanation
Gas absorption efficiency depends on how strongly the dissolved gas molecules interact with the liquid solvent. Here, you're comparing two systems using their molecular properties—dipole moment () and polarizability ()—to predict which will have stronger intermolecular attractions. The key insight is that dipole-induced dipole interactions scale with , while dispersion forces depend on the liquid's polarizability. By calculating the interaction strength for each gas-liquid pair, you can rank which system will dissolve and capture the hazardous gas more effectively.