Volume fraction = volume of the element / volume of the alloy
Volume = density * mass
Base: 100 grams of alloy
mass of tin = 15 grams
mass of lead = 85 grams
volume = mass / density
Volume of tin = 15g / 7.29 g/cm^3 = 2.06 cm^3
Volume of lead = 85 g / 11.27 g/cm^3 = 7.54 cm^3
Volume fraction of tin = 2.06 cm^3 / (2.06 cm^3 + 7.54 cm^3) = 0.215
Volume fraction of lead = 7.54 cm^3 / (2.06 cm^3 + 7.54 cm^3) = 0.785
As you can verify the sum of the two volume fractions equals 1: 0.215 + 0.785 = 1.000
0.500 moles is roughly .5*6.022*10^23=3.011*10^23 atoms. This is independent of STP.
NaCl is table salt so you need 4Na and 4 Cl, So Na₄Cl₄
Mg 10.9g/24.31=0.018/0.018=1
Cl 31.8g/35.45=0.897/0.018=49.83=50
O 57.3g/16.00=3.581/0.018=198.94=199
empirical formula=MgCl50O199
I think it's right
