Question

How to calculate the gravimetric factor

Answer 1

gravimetric factor is not constant, you need to have certain relationship example:
m(Fe2O3) = m(FeO) * (M(Fe2O3)/2* M(FeO))
where (M(Fe2O3)/2* M(FeO)) is gravimetric factor.
i gave you that example cause i was just doing one problem with gravimetric factor ;)

Answer 2

Just say we wanted to figure out the mass of carbon present in CO2,
we set up the equation:

\[(\frac{Molecular Mass of Carbon}{Molecular Mass of CO_2})Grams of CO_2 = Grams of Carbon\]

if you wanted to convert back to grams CO2 from grams of Carbon you would just flip the ratio so the molecular mass of CO2 is ontop and Grams of Carbon are on the bottom and then just multiply that by Grams of C