CxH(2x+2) ⇒ CxH2x + H2 ↑
initial : n moli alcan m = (14x+2)n
final : 0,45n moli alchena + 0,45n moli H2 + 0,55n alcan netransformat
m final = m initial = (14x+2)n
n = 1,45n moli M = m/n = (14x+2)/1,45
M = q·22,4 = 1,786·22,4 = 40 g/mol
14x + 2= 1,45·40
14x = 56 x = 4 C4H10