Question 1
What is the concentration of Ca
2+ in ppm (mg/L) in cave water saturated with calcite (calcium carbonate,
Ksp = 4.7 × 10
-9)?
◦ 7.5 ppm
◦ 6.9 ppm
◦ 5.0 ppm
◦ 3.8 ppm
◦ 2.7 ppm
Question 2
What is the concentration of free Zn
2+(aq) if 0.020 M Zn
2+ solution is mixed with an equal volume of 2.0 M NH
3(aq)?
Kf for [Zn(NH
3)
4]
2+ is 4.1 × 10
8.
◦ 2.5 × 10
-11 M
◦ 2.9 × 10
-11 M
◦ 1.7 × 10
-10 M
◦ 9.6 × 10
-11 M
◦ 2.4 × 10
-9 M