Mass of an atomic layer of a baloon

[Myrddin]

An inflated smooth toy balloon is coated with a single atomic layer of aluminium. Esitimate the mass of Al that would be required. The density of Al is 2.7 x10^3kg/m^3 and its molar mass if 27 grams for mol.


I assusmed the balloon was a sphere of radius 10cm, found surface area then mutliplied by approximate radius of an atom to find volume of the layer. Then used volume x density to find mass, but this method doesn't make use of the molar mass in the question? Any other methods you can see?

 

[ehild]

I assumed the balloon was a sphere of radius 10cm, found surface area then multliplied by approximate radius of an atom to find volume of the layer. Then used volume x density to find mass, but this method doesn't make use of the molar mass in the question? Any other methods you can see?

The approximate radius of the aluminium atom follows from the molar mass and density.

ehild