Answer
a) $Al + Fe_2O_3\rightarrow Al_2O_3+Fe$
b) $C+H_2O\rightarrow CO+H_2$
c) $SiCl_4+2\ Mg\rightarrow 2\ MgCl_2+ Si$
Work Step by Step
a) $Al + Fe_2O_3\rightarrow Al_2O_3+Fe$
Already balanced
b) $C+H_2O\rightarrow CO+H_2$
Already balanced
c) $SiCl_4+Mg\rightarrow MgCl_2+ Si$
Balancing Cl: $2\ MgCl_2/1\ SiCl_4$
$SiCl_4+2\ Mg\rightarrow 2\ MgCl_2+ Si$
