n moli C3H6 + H2 ⇒ C3H8
3n moli H2
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amestec gazos final : C3H8 (x moli ) + H2 (3n-x) + C3H6 [(n-x) moli) .....
n amestec final = (4n-x) moli m = 42n+2·3n=48n (g) M=0,519·28,9 = 15g/mo
48n/(4n-x) = 15 3,2n = 4n-x x = 0,8n
η =x·100/n = 80%