87 -- In two separate containers, moles of alkene and acetylene gas equal to a sufficient amount of liquid bromine react. If the mass of product from the acetylene reaction is approximately 1.71 times the mass of product from the alkene reaction with liquid bromine, which alkene is it?
$(H = 1, C = 12, Br = 80 \ ; \ \text{g.mol}^{-1})$
$$C_\gamma H_\gamma(g) + \gamma Br_\gamma(l) \rightarrow C_\gamma H_\gamma Br_\mathfrak{f}(l)$$ $$C_n H_{\gamma n}(g) + Br_\gamma(l) \rightarrow C_n H_{\gamma n} Br_\gamma(l)$$
| (1) Hexene | (2) Pentene | (3) Butene | (4) Propene |