To find the mass of isopropyl alcohol, we can use the formula:
Mass = Density × Volume
In this case, the density of isopropyl alcohol is 0.79 g/ml, and the volume we have is 39.5 ml. Plugging these values into the formula gives:
Mass = 0.79 g/ml × 39.5 ml
Now, performing the multiplication:
Mass = 31.205 g
Therefore, the mass of 39.5 ml of isopropyl alcohol is 31.205 grams.