chemistry
posted by katie .
What is the mass percent of a solution if 42.9 grams of aspirin is dissolved into 175 mL of ethanol? (Density of ethanol is 0.789 g/mL

You are calculating w/w%, which is
mass (A) x100%/(total mass A + M)
From the density we can find the mass of ethanol
M=0.789 g/ml x 175 ml
A=42.9 g