Answer
$Fe_{2}O_{3}(s)+ 3H_{2}(g)\ -->\ 2Fe(s) + 3H_{2}O(l)$
Work Step by Step
Write out the equation without coefficients. Add a coefficient of 2 to the solid iron to balance the 2 irons in the iron(III) oxide. Add a coefficient of 3 to the water to balance out the oxygen in the iron(III) oxide. Finally add a coefficient of 3 to the gaseous hydrogen to balance out the two hydrogen in water which are being multiplied by three.