In an isothermal process, the internal energy of gas molecules Select one: O a. Decreases O b. Remain constant O c. Increases O d. May increase/decrease depending on the properties of gas

a) Briefly explain the physical processes that lead to an equilibrium value for the volume V of a solid. b) Potassium chloride is an ionic salt, whose internal energy per mole is well-modelled by the function aN₁Q+Q™ 4π€0 r +6Be-r/ro where a is the Madelung constant for this material, Q are the electric charges of the potassium (K+) and chloride (Cl-) ions, N₁ is Avogrado's number, r the closest distance between oppositely charged ions, and the permittivity of free space. We have introduced the constants B and ro. U(r) = Explain the physical origin of the two terms in this equation. U = - c) By assuming that potassium chloride has the same structure as sodium chloride, explain why the internal energy per mole may be written in terms of the volume V as -1/3 aNte² (2NA) (2N₁) 4π€0 +6B exp 1 [] To 2NA

Subject: mechanical

Answer the last two parts of the question (d) the ideal gas properties of carbon monoxide table (Table A-21). Calculate the percent error between answers i) d & a, li) d & b and i) d & c.