I'm confused about this problem because if you add 7.5% of 375 to 375, won't the final solution then have a concentration lower than 7.5 since you've added volume? The density of ethylene glycol (antifreeze, HOCH2CH2OH) is 1.09 g/mL. How many grams of ethylene glycol should be mixed with 375 mL of water to make a 7.50% (v/v) mixture? Answer: 375 mL x 0.0750 = 28.125 mL ethylene glycol 28.125 mL ethylene glycol x 1.09 g ethylene glycol = 30.7 g ethylene glycol