Given the following recipe: H2SO4 = 0.00200 mol/L

Solution equilibrated with an excess of CaCO3(s) (calcite). The Ksp of calcite is 10-8.35

i) List the species present at equilibrium and find n equations for your n unknowns.

(Hints: find out what carbonate does on your pKa chart.)

ii) You will have one “b” expression for each “non-simple” mole balance equation

and one more for the charge balance equation. Write these down.

iii) Choose one parameter to guess in each “b” expression (for example, for the b

expression from your charge balance, you will choose pH)

iv) Write down the list of equations you will use in Excel to calculate the

concentrations of all of your species (remember that you will only use equilibrium

expressions and simple mole balance equations to derive these equations; you will

not use the equations you are using as your “b” expressions). For example, since

you guessed pH, you can calculate [H+] = 10-pH and [OH-] = 10-14.00/[H+]

Use a spreadsheet and Excel’s Solver function to determine the equilibrium pH and
concentrations of all species in a solution with the recipe.