9. Given that Agl would precipitate first than AgCl in a solution containing equimolar concentrations of I and Cl, it can be concluded that: O Ksp Agt > Ksp.AgCl O Ksp.Agl

Describe a nonchemical system that is not in equilibrium, and explain why equilibrium has not been achieved.

The following data apply to the unbalanced equation A(g)B(g) (a) On the basis of the data, balance the equation (simplest whole-number coefficients). (b) Has the system reached equilibrium? Explain.

The ore cinnabar (HgS) is an important source of mercury. Cinnabar is a red solid whose solubility in water is 5.5 X 10-2 mol L-1. Calculate its \p. What is its solubility' in grams per 100 g of water?

Because barium sulfate is opaque to X-rays, it is suspended in water and taken internally to make the gastrointestinal tract visible in an X-ray photograph. Although barium ion is quite toxic, barium sulfate’s /Csp of 1.1 X 10-,<) gives it such low solubility' that it can be safely consumed. What is the molar solubility' of BaSO4. What is its solubility' in grams per 100 g of water?

In a particular experiment, the equilibrium constant measured for the reaction, Cl2(g)+NO2(g)Cl2NO2(g), is 2.8. Based on this measurement, calculate AG° for this reaction. Calculate AG° using data from Appendix E at the back of the book and discuss the agreement between your two calculations.

The following is a thought experiment. Imagine that you put a little water in a test tube and add some NaF crystals. Immediately after you add NaF, you observe that the crystals begin dissolving. The quantity of solid NaF decreases, hut before long, it appears that no more NaF is dissolving. The solution is saturated. The equation for the dissolution of NaF in water is NaF(s) —* Na (aq) + F~(aq). As NaF dissolves, what do you think happens to the rate of dissolution? Describe w hat is occurring on the molecular level. Assume that the reverse reaction, Na+(aq) + F“(aq) —* NaF(s), also occurs as the crystal dissolves. In other words, both dissolution and precipitation are taking place. When it appears that there is no more change in the quantin’ of NaF dissolving (the solution is saturated), w hat has happened to the rates of the forward and reverse reactions? Explain your answer.

Which of the systems described in Exercise 13.16 give homogeneous equilibria? Which give heterogeneous equilibria?

A 0.010 M solution of the weak acid HA has an osmotic pressure (see chapter on solutions and colloids) of 0.293 atm at 25 C. A 0.010 M solution of the weak acid HB has an osmotic pressure of 0.345 atm under the same conditions. (a) Which acid has the larger equilibrium constant for ionization HA[HA(aq)A(aq)+H+(aq)] or HB[HB(aq)H+(aq)+B(aq)]? (b) What are the equilibrium constants for the ionization of these acids? (Hint: Remember that each solution contains three dissolved species: the weak acid (HA or HB). the conjugate base (A- or B- and the hydrogen ion (H+). Remember that osmotic pressure (like all colligative properties) is related to the total number of solute particles. Specifically for osmotic pressure, those concentrations are described by molarities.)

A small quantity of a soluble salt is placed in water. Equilibrium between dissolved and undissolved salt may or may not be attained. Explain.