Question

balance the chemical equation.
a 1,2,1,2
b 1,1,3,1
c 3,1,3,2
d 2,3,2,3
mg + fe₂o₃ -> mgo + fe

Explanation:

Step1: Balance oxygen atoms

There are 3 oxygen atoms in $Fe_2O_3$. To balance oxygen, we need 3 moles of $MgO$ since each $MgO$ has 1 oxygen atom. So the coefficient of $MgO$ is 3.

Step2: Balance magnesium atoms

Since the coefficient of $MgO$ is 3, to balance magnesium, the coefficient of $Mg$ must be 3 as well.

Step3: Balance iron atoms

There are 2 iron atoms in $Fe_2O_3$, so the coefficient of $Fe$ should be 2.
The balanced equation is $3Mg + Fe_2O_3
ightarrow3MgO + 2Fe$.

Answer:

C. 3, 1, 3, 2