$CH_3COONa+NaOH\buildrel{{CaO, t^o}}\over\to CH_4+Na_2CO_3$
$2CH_4\buildrel{{1500^oC}}\over\to C_2H_2+3H_2$
$2C_2H_2\buildrel{{CuCl_2, t^o}}\over\to CH\equiv C-CH=CH_2$
$CH\equiv C-CH=CH_2+H_2\buildrel{{Pd/PbCO_3, t^o}}\over\to CH_2=CH-CH=CH_2$
$nCH_2=CH-CH=CH_2\buildrel{{t^o, p, xt}}\over\to (-CH_2-CH=CH-CH_2-)_n$