What is the concentration in M of KCl in a solution made by mixing 25.0ml of 0.175M KCl with 50.0ml of 0.175M KCl

Question

anonymous · Answer

How do you think this one is solved?

anonymous · Answer

i would thing 25 times .175 divided by 50

anonymous · Answer

thats what i would think also

anonymous · Answer

it doesnt work though

anonymous · Answer

try putting in 0.175 M KCl

xishem · Answer

If you mix two solutions with the same concentration, I'd think that the concentration would stay the same. There's no reason it wouldn't.

If you separated a 1L sample of .175 M KCl into two 500mL samples, they both will be the same concentration. Put them back together, and they are still .175M.

To do it more analytically, try this:

Find how many moles of KCl are in each of the two solutions. This is how many moles will be present in the final, mixed solution. Then using the molar concentration equation...$$c_i=\frac{mols\ KCl}{V_{sol'n}}$$And obviously, if you mix a 50mL sample with a 25mL sample, you will get 75mL, assuming the volumes are additive.

You'll find that the concentration is indeed the 0.175M.