How do you find the percent composition (by mass) of each element in iron(II) nitrate?

1 Answer
May 16, 2017

Answer:

#"%composition (m/m)"="Mass of element in 1 mol of compound"/"Molar mass of compound"xx100%.#

Explanation:

For #Fe(NO_3)_2#............

#%Fe=(55.85*g*mol^-1)/(179.87*g*mol^-1)xx100%=31.0%#

#%N=(2xx14.01*g*mol^-1)/(179.87*g*mol^-1)xx.............=??#

#%O=(6xx16.00*g*mol^-1)/(179.87*g*mol^-1)xx.............=??#

Should the individual percentages sum up to #100%#? Why?