posted by Katie .
A square of aluminum foil measuring 3.20 inches on each side weighs 275 mg. The density of aluminum is 2.70 g/cm3. Find the thickness (in micrometers) of the foil.
Convert 3.20 inches to cm and square that to arrive at the area of the Al square.
volume Al = mass/density.
Solve for volume.
Then volume = area x thickness.
You know volume and area, solve for thickness and convert to micrometers.