Question

How do I find the molarity of Fe(SCN)2+?

I know the molarity of SCN=0.1 and the molarity of Fe is 0.0001. The volume of SCN is 5 mL and the volume of the Fe is also 5mL. I also think that I use M1V1=M2V2.

Answer 1

You have diluted each by a factor of 2 (that is, from 5 to 10); therefore, (Fe^+3) = (1/2)*0.0001 and (SCN^-) = (1/2)*0.1.
M1V1 = M2V2 works but this one is so easy you don't need an equation.

Answer 2

Thanks. Would it matter which molarity I use if I used M1V1 = M2V2