Question

o substanta organica ce contine 82.76% carbon si 17.24%hidrogen are densitatea relativa fata de oxicen 1.81

Answer 1

notam hdroc. CxHy

d(o2) = miuCxHy / miu O2

=> miuCxHy = d(o2)xmiu(O2) = 1,81x32 = 58 g/mol

 100% ............ 82,76% C .......... 17,24% H

58 g CxHy ........ 12x C .............. y H

=> x = 4 si y = 10

=> CxHy = C4H10

Answer 2

-calculez masa molara din densitatea relativa

d=M/M,O2---> d= 1,81x32g/mol= 58g/mol

-transform procentele de masa in numar de moli, impartind prin masele atomice

nC=82,76/12= 6,9    SI    nH= 17,24; impart prin cel mai mic

nC=1.     nH= 2,5

F.B.   (C1H2,5)n---> (12+2,5)g=58---> n=4----> C4H10