Chapter 27, Problem 1ASA

Solid KSCN was added to a(2.20x10^0) M Co2+ solution so that it was also initially (2.20x10^0) M SCN-. These ions then reacted to give the complex ion Co(SCN)2+, whose formation constant is 1.0x102. What is the concentration of Co2+(aq) at equilibrium? You may assume x to be small. Express your answer to three significant figures.

How do you figure out the function of complexed and uncomplexed Fe3+as a function of log(SCN-) in the reaction:   (Fe3+)+(SCN^-)=(Fe(SCN)2+ ) The formal question is: Use the value of K eq determined in this experiment to calculate the fraction of Fe(III) that is complexed and the fraction of Fe(III) that is uncomplexed in solutions containing a large excess of thiocyanate ion over Fe(III). Begin by deriving an algebraic equation for these fractions (i.e., f comp and f uncomp) as a function of thiocyanate concentration. I do not need numbers. I just want to know how to approach this problem.

A solution contains 0.25 M Ni(NO3)2 and 0.25 M Cu(NO3)2. A. Can the metal ions be separated by slowly adding Na2CO3 aq solution? Assume that for successful separation 99% of the metal ion must be precipitated before the other metal ion begins to precipitate, and assume no volume change on addition of Na2CO3 solution. Pls show step by step.    Ksp  of CuCO3 = 1.4 x10-10    Ksp  of NiCO3 = 1.42X 10-7 B.  If you need to redissolve the salt that was first precipitated, what pH will you use and why ?