Calculate the density.

Question

Laken pipets 5.00 mL of ethanol into a flask weighing 15.25 g. She finds the mass of the flask plus ethanol is 19.17 grams. Calculate the density of ethanol alcohol.

Answer 1

The flask plus the ethanol is 19.17 g and the flask alone is 15.25 g.  That means that the mass of the ethanol alone is 19.17 - 15.25 = 3.92 g

 

The volume of the ethanol is 5.00 ml, so to find the density, just divide the mass by the volume:  3.92 / 5.00 = 0.784 g / ml.