Convert the following molar concentration 0.0036 M Ca(OH)2 solution to units of ppm. (Answer is 270 ppm)
You know the molar concentration, 0.0036 M, which means you have 0.0036 moles in one liter of solution. One liter is 1000 mL or 1000 g since the density of water is 1g/ml
1. Find the formula mass of Ca(OH)2
2. Multiply the formula mass * the molarity (0.0036 M), this tells you how many grams in 1000 grams. Let this be X grams.
3. Set up a ratio: X grams (from #2)/1000 g = Y grams/1000000 g
Solve for Y, the # of grams in one million grams of water, which is also the ppm.