# Convert the following molar concentration 2.9 x 10^-6 M Cd(NO3)2 solution to units of ppm. (Answer is 0.69 ppm)

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You know the molar concentration, 2.9 x 10^-6 M, which means you have 2.9 x 10^-6 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 Cd(NO3)2

2. Multiply the formula mass * the molarity (2.9 x 10^-6 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.

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