$A{l}_{(s)}+Mn{O}_{2(aq)}$

$12$

$Cu(II{)}_{(s)}+C{l}_{2(g)}$

$12$

$FeC{l}_{3(aq)}+Mg{S}_{(aq)}$

$12$

$Pb{I}_{4(aq)}+CuC{l}_{(aq)}$

$12$ Y

$H_{3}P{O}_{4(aq)}+Pb(OH{)}_{4(s)}P{b}_3(P{O}_4{)}_4+H_{2}O$

$12$

$N{a}_{2}C{O}_{3(aq)}+Au{F}_{3(aq)}$

$12$

$C_2{H}_{6(g)}+O_{2(g)}C{O}_2+H_{2}O$

$12$