Question

part 2: practice
balance these equations. show your work (atom counts, steps, and final answer).

1. h2+o2→h2o

work:
answer:

1. fe+o2→fe2o3

work:
answer:

Explanation:

Step1: Analyze hydrogen and oxygen atoms in first equation

On the left - hand side, we have 2 hydrogen atoms and 2 oxygen atoms in $H_2 + O_2$. On the right - hand side, in $H_2O$, we have 2 hydrogen atoms and 1 oxygen atom. To balance oxygen, we put a 2 in front of $H_2O$ to get 2 oxygen atoms on the right. Then we need to adjust hydrogen. We put a 2 in front of $H_2$.
$2H_2+O_2
ightarrow2H_2O$

Step2: Analyze iron and oxygen atoms in second equation

In $Fe + O_2
ightarrow Fe_2O_3$, on the left - hand side, we have 1 iron atom and 2 oxygen atoms. On the right - hand side, we have 2 iron atoms and 3 oxygen atoms. First, to balance oxygen, we find the least common multiple of 2 and 3, which is 6. So we put a 3 in front of $O_2$ and a 2 in front of $Fe_2O_3$ to balance oxygen. Then we balance iron by putting a 4 in front of $Fe$.
$4Fe + 3O_2
ightarrow2Fe_2O_3$

Answer:

1. $2H_2+O_2

ightarrow2H_2O$

1. $4Fe + 3O_2

ightarrow2Fe_2O_3$