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Science-Related Homework Help Chemistry Topic started by: mickeyK on Oct 19, 2012



Title: How to calculate molarity of ions in a solution?
Post by: mickeyK on Oct 19, 2012
All I'm given is this:

A solution contains 0.010 M CaCl2. calculate the molarity of the ions in solution. The ionic strength of the solution, the activity coefficient of the calcium ion and its activity.

I'm confused on how to solve this. We're given a sample calculation but it is not a very thorough explanation.


Title: How to calculate molarity of ions in a solution?
Post by: ilikelamp on Oct 19, 2012
CaCl2 breaks down into Ca+ and 2Cl- in a solution which total 3 ions.

so if there are 0.010 M (= mols/L) of cacl2 then multiply by 3 to

give you the molarity of toatal ions.

Mathematically:

(0.010mols CaCl2 / L)(3 ions / CaCl2) = 0.030 mols/L (= M) ions.

good luck!