1. Parts per Million Concentration

2. Parts per Million (ppm) is the ratio of the number of grams of solute for every one million grams of solution. parts per million = grams of solute x 1000000 grams of solution Ex.1) What is the number of ppm of NaCl in the solution with 117 g of NaCl dissolved in 500. mL of water? ppm = g solute x 1000000 g sol’n x = ______ x 1000000 117 g 617 g x = 190000 ppm

3. Parts per Million Concentration Ex.2) What is the number of ppm of C 2 H 4 (OH) 2 in the solution with 55.5 g (50.0 mL) of liquid C 2 H 4 (OH) 2 dissolved in 150.0 mL of water ? ppm = g solute x 1000000 g sol’n x = __________ x 1000000 55.5 g 205.5 g x = 270000 ppm

4. Parts per Million Concentration Ex.3) If 3.0 mg (0.0030 g) of Cr +6 is dissolved in 3.0000 L (3000.0 mL) of water what is the concentration of the hexavalent chromium (Cr +6 ) in ppm? ppm = g solute x 1000000 g sol’n x = ____________ x 1000000 0.0030 g 3000.0030 g x = 1.0 ppm