Help finding the volume

The question asks, you want to electroplate a spoon with gold.

You want the gold to be 10 um thick on the spoon (40 cm^2).

I know how to solve this problem except for finding the volume for the equation mass = volume x density

You are covering a 40 cm^2 area with a 10 µm thick gold plate.

10 µm = 0.010 mm = 0.000010 cm.

so volume = 40 * 0.000010 = 0.0004 cm^3.

density = mass / volume so mass = density * volume.

density of gold is 19.30 g /^cm3.

mass gold = 19.30 g / cm^3 * 0.0004 cm^3 =0.00772 g.

In this case, you probably won't want to use that equation, since we have no mass and no density... Instead, try V = length x width x height (think of it like a rectangular prism or something to that effect), and act like the (l x w) is the 40 cm^2, so you end up with 40 cm^2 x 10 um.

1 micron= 0.00001 cm
10 microns= 0.0001 cm
40 cm^2 x 0.0001 cm=0.04 cc of Au
density of Au=~17 g/cc
mass= 0.04cc x 17g/cc= 0.68 g Au