Grains of California beach sand are approximately spheres with a radius of, on average, 50 Μm. They are made of silicon dioxide, which has a density of 2600 kg/m^3. What mass of sand grains would have a total surface area (i.e. the total surface area of all the individual spheres) equal to the surface area of a cube 1.00 m on an edge? The surface area of a single sphere is 4πr^2.
The answer is 0.260 kg.
Show work.