To get density, one usually always measures mass first since there are so many tools available to do so. I suppose,though, that through a system of trial and error one could get an approximate...
They use a number called a mole. This many atoms of an element equals its atomic weight in the periodic table. Molecular weight is the sum of atomic weight. Silver has an atomic weight of 108...
see density is simply the number of particles(atoms,molecules) in a unit space(volume).The greater the no of particles in an area the greater the density. The formula of density can be denoted...