Question

How do you show the work for the molar mass of Calcium (Ca)?

Answer 1

there's no real "work" done, just look it up on a periodic table.

Answer 2

if you need the molar mass of a COMPOUND, you'd need to take the masses of the pieces and add them together, which means a little work:\[MM_{CaO} = MM_{Ca} + MM_{O} = 40g*mol^{-1} + 16g*mol^{-1} = 56 g*mol^{-1}\]