Question #31a4e

1 Answer
Jun 21, 2017

BaF_2BaF2......

Explanation:

As always we assume an 100*g100g mass of stuff, and work out the atomic composition......

"Moles of barium"=(78.3*g)/(137.3*g*mol^-1)=0.570*molMoles of barium=78.3g137.3gmol1=0.570mol

"Moles of fluorine"=(21.7*g)/(19.00*g*mol^-1)=1.140*molMoles of fluorine=21.7g19.00gmol1=1.140mol

You note that I divided thru by the ATOMIC mass.......

And we simply divide thru by the element present in LEAST molar quantity (barium) to get ........

BaF_2BaF2...........this is an ionic compound that would be formulated as same. If we do this for an organic formula, we need a molecular mass BEFORE we deduce the molecular formula......

"molecular formula"=nxx"empirical formula"molecular formula=n×empirical formula............