n(CO2)=7,84/22,4=0,35;  n(H2O)=3,6/18=0,2;

                     0,35   0,2

СxHy+O2 = CO2+H2O     : 0,05

                       7          4

CxHy +O2= CO2+ H2O

CxHy +O2= 7CO2 + 4H2O

x=7; y=8;

                Ответ: С7Н8( СН3-С6Н5)-метилбензол.

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