se trece da la rapoartele masice la cele molare,impartind mC la12 si mH la 1
nC:nH= 92,3/12: 7,69/1
= 7,69: 7,69 prin simplificare
= 1:1-----> formula bruta (CH)n
din masa molara aflu n
n(12gC+1gH)=78---> n=6----> formula molculara C6H6
O ALTA VARIANTA......MAI SIMPLA :
daca in 100g substanta..........92,3gC......7,69gH
78g........................m,C=72g......m,H=6g
x,mol= 72g/12g/mol= 6mol C
y,mol= 6g/1g/mol= 6molH------> FORMULA MOLECULARA C6H6
