What is Density?
¥Density (r) = Mass (M) per unit Volume (V)
¥      r = M/V
¥      r = Greek letter ÒrhoÓ
¥Typical Units: kg/m3, gm/cm3
¥Mass  = 
¥ # molecules (mole) « molecular mass (gm/mole)
¥
¥    Avogadro number (6.023x1023 molecules/mole)