Convert the following molar concentration 0.0036 M Ca(OH)2 solution  to units of ppm. (Answer is 270 ppm)

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ndnordic | High School Teacher | (Level 2) Associate Educator

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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.