

Calculating dilutions and concentration Dilutions If you need to dilute a stock solution, the formula to use is: V_{1}C_{1}=V_{2}C_{2} where V_{1} is the volume of the stock solution, and C_{1} is its concentration and V_{2} is the final volume you are making, and C_{2} is the final concentration you want.
Concentrations % concentration, there are 2 possibilities: 1) % per weight, which is used only for solids. x% = x grams of solute/100 ml total volume 2) % per volume, which is used only for liquids. X% = x ml of solute/100 ml total volume If you need to calculate a % per weight or a molar concentration of a liquid solute, then you have to find out the density of the solution you will dilute, or measure it (i.e. weigh 1 ml or so). 3) Molar concentration # moles / 1 liter of solution #moles of x grams of a substance is: x grams/molecular weight (molecular weight is expressed in grams/mol) 
Copyright: STG Lab 2012
