Question

select the correct answer.
which is the next logical step in balancing the given equation?
$3\ce{co_{(g)}} + \ce{fe_{2}o_{3(s)}} \
ightarrow \ce{fe_{(s)}} + 3\ce{co_{2(g)}}$
a. place the coefficient 2 in front of iron(iii) oxide.
b. leave it alone, as it is already balanced.
c. place the coefficient 2 in front of elemental iron.
d. replace the coefficient 3 in carbon monoxide with 6.

Explanation:

To balance the chemical equation \( 3\text{CO}_{(g)} + \text{Fe}_2\text{O}_{3(s)}
ightarrow \text{Fe}_{(s)} + 3\text{CO}_{2(g)} \), we check the number of each atom on both sides. For Fe: left side has 2 (from \(\text{Fe}_2\text{O}_3\)), right side has 1 (from \(\text{Fe}\)). To balance Fe, we need to place a coefficient of 2 in front of \(\text{Fe}\) (elemental iron) to make the number of Fe atoms equal (2 on both sides). Option A is incorrect as \(\text{Fe}_2\text{O}_3\) already has 2 Fe atoms and doesn't need a coefficient change. Option B is incorrect because Fe atoms are unbalanced. Option D is incorrect as CO and \( \text{CO}_2 \) are already balanced (3 C and 6 O on both sides). So the next step is to place 2 in front of Fe.

Answer:

C. Place the coefficient 2 in front of elemental iron.