1. 30.0 ml of ethyl alcohol(density=0.790g/ml)are added to a graduated cylinder that weighs 44.28 grams. what will be the mass of the graduated cylinder plus the alcohol(in grams)?

Answer 1

Density = mass/volume
mass = volume * density
volume = mass/density

You were given both the volume and density of ethyl alcohol, and you're looking for the amount the mass of ethyl alcohol added to the graduated cylinder. So, plug in the numbers for mass:

30mL * 0.790g/mL = 23.7g ethyl alcohol
23.7g ethyl alcohol + 44.28g graduated cylinder = 67.98g