CnH2n(OH)2 + 2 K ---> CnH2n(OK)2 + H2
masa molara diol = 12n+2n+2*(16+1)=14n+34
14n+34 g diol......22,4 l H2
18 g diol............4,48 l H2
403,2=62,72n+152,32=>62,72n=250,88=>n=4
=>diolul cautat este C4H8(OH)2 sau scris altfel C4H10O2
NE=2+4*2-1*10/2=2+8-10/2=0=>diol saturat