What number of magnesium ATOMS are contained in a #12*g# mass of the metal?

1 Answer
Mar 16, 2017

#"Number of atoms......= "3.011xx10^23#

Explanation:

#"Number of atoms of Mg"# #-=# #"Mass of metal"/"Molar mass of metal"xxN_A#,

where #N_A-="Avogadro's number"=6.022xx10^23*mol^-1#

And so to business,

#"Number of atoms of Mg"# #-=# #(12*g)/(24.31*g*mol^-1)xxN_A#,

#=1/2*cancel(mol)xx6.022xx10^23*cancel(mol^-1)#

#=3.011xx10^23#, a #"noomber"# as required.........