Suppose if 50.0 mL of 0.250 M CoCl2 solution is added to 25ml of 0.35M NicL2 solution. Calculate the concentration in moles per litre, of each of the ions present after mixing. Assuming that the volume are additive.

Answer 1

So each solution is diluted to 75 mL. The new concentrations are
0.250 M CoCl2 x (50/75) = 0.167 M
0.35 M NiCl2 x (25/75) = 0.117 M
(Co^2+) = 0.167 M
(Ni^2+) = 0.117
(Cl^-) = 2*0.167 from CoCl2 + 2*0.117 from NiCl2.