Complete the following reactions:
$(i) \, H_{2(g)} + M_m O_{o(s)} \xrightarrow{\Delta }$
$(ii) \, CO_{(g)} + H_{2(g)} \xrightarrow[catalyst]{\Delta }$
$(iii) \, C_3 H_{8(g)} + 3 H_2 O_{(g)} \xrightarrow[catalyst]{\Delta }$
$(iv) \, Zn_{(s)} + NaOH_{(aq)} \xrightarrow{heat}$

$(i) \, H_{2(g)} + M_m O_{o(s)} \xrightarrow{\Delta } m M_{(s)} + o H_2 O_{(g)}$
$(ii) \, CO_{(g)} + 2 H_{2(g)} \xrightarrow[catalyst]{\Delta } CH_3 OH_{(l)}$
$(iii) \, C_3 H_{8(g)} + 3 H_2 O_{(g)} \xrightarrow[Ni, 1270 \ K]{\Delta } 3 CO_{(g)} + 7 H_{2(g)}$
$(iv) \, Zn_{(s)} + 2 NaOH_{(aq)} \xrightarrow{heat} Na_2 ZnO_{2(aq)} + H_{2(g)}$