-Calculez masa molara a hidrocarburii ,din densitatea relativa, stiind
M,H2= 2g/mol
d= M,compus/M,H2---> M,compus= 36x2--> 72g/mol
-deduc numarul de C din compus,stiind M,CO2= 44g/mol
n(niu)CO2= m/M
n= 22g/44g/mol= 0,5molCO2=0,5molC
7,2gcompus........0,5molC
72g.......................n=5molC
-Calculez moliH din masa molara 72g= 5x12gC+ m,H-->m,H= 12g
n.H= 12g/1g/mol= 12molH
COMPUSUL ESTE C5H12-pentan
CH3-CH2-CH2-CH2-CH3 n.pentan 2Cp,3Cs
CH3-CH(CH3)-CH2-CH3 2metil butan 3Cp, 1Cs, 1Ct
CH3-C(CH3)2-CH3 2,2 dimetil propan sau neopentam 4Cp.1Cc