The change in standard free energy for thegiven reaction is-1 kJ/mol at room tem-perature.What is the equilibrium constantfor the reaction at the same temperature?(R= 8.3 J·K−1mol−1)1.0.012.1.00196.0 pointsConsider the reaction,The equilibrium constant,K, is 2.If theconcentrations of A, B and C are 2 M, 2 Mand 10 M, respectively, which of the followingwould occur?0206.0 pointsWhich of the following gases are more solublein water when their partial pressure above thesolution is increased?
Version 406 – Exam 1 – laude – (51635)72.all of themcorrect3.Cl2,NO2,SO3,HI4.HI,NH35.NO2,O2,HI6.NO2,SO3Explanation:Henry’s Law states that the solubility ofgases increase as their partial pressure abovethe solvent increases.0216.0 pointsWhat would be the pH of a solution of hypo-bromous acid (HOBr) prepared by dissolving9.7 grams of the acid in 20 mL of pure wa-ter (H2O)? The Ka of hypobromous acid is2×10−184.108.40.206correct4.15.10Explanation:9.7 g HOBr×1 mol97 g= 0.1 mol HOBr0.1 mol HOBr0.02 L H2O= 5 M HOBr[H+] = (Ka·Ca)1/2= (2×10−9·5)1/2= (10−8)1/2= 10−4pH =-log[H+] =-log(10−4) = 40226.0 pointsWhen making ice cream, salt (NaCl) is addedto the water and ice mixture. The equilibriumtemperature of this ice-salt water mixture is1.less than 0◦C because salt has a very lowspecific heat.2.less than 0◦C because the dissolved saltlowers the freezing point of the ice/water mix-ture.correct3.greater than 0◦C because salt melts ice.4.greater than 0◦C because NaCl melts at ahigher temperature than water.5.less than 0◦C because salt reacts withwater.6.0◦C because it is at equilibrium.Explanation:The equilibrium temperature of a water-ice mixture is 0◦C (i.e., the freezing point).When salt is added to the mixture, the freez-ing point (i.e., equilibrium temperature) islowered. Salt does melt ice, but not by rais-ing its temperature, so don’t let that choiceconfuse you.Salt melts ice by lowering thefreezing point.0236.0 pointsMolar Gibbs energy,GmTemperature,Tvaporpure liquidsolventReferring to the graph above, and usingyour knowledge of ΔHsolution, complete thefollowing statement concerning boiling pointelevation:Adding solute decreases the molar Gibbsenergyoftheliquidatalltemperaturesby(increasing/decreasing)themolar(en-thalpy/entropy) of the liquid.This causes
Version 406 – Exam 1 – laude – (51635)8Explanation: