[crh1415]

Hey there, I'm having some serious problems with my homework assignment.

I'm supposed to:

"Calculate the concentraion of all ions present in each of the following solutions of strong electrolytes"

The first problem is:

0.300 mol of Ca(NO₃)₂ in 100.0 mL of solution

Honestly, I'm totally clueless as to where to begin. I know that the two ions I need to calculate the molarity for are Ca²⁺ and NO₃^-

To begin would I divide 0.300 moles by 0.100 L to get the overall molarity?

All help is appreciated!

[Borek]

To begin would I divide 0.300 moles by 0.100 L to get the overall molarity?

Yes. Don't forget that there are twice more NO₃^- then Ca²⁺.

[mike]

c = n/v so when you divide the number of moles of Ca(NO₃)₂ by the volume this will give you the concentration in solution of Ca(NO₃)₂. For every one mole of Ca(NO₃)₂ in solution you have one mole of Ca²⁺ and two moles of NO₃^-. Which means that the concetration of Ca²⁺ should be the same as Ca(NO₃)₂ and the concentration of NO₃^- should be twice the concentration of Ca(NO₃)₂

[crh1415]

Ok great, thank you very much for the help Borek and Mike!