To balance the chemical equation [tex]\( \text{Mg} + \text{O}_2 \rightarrow \text{MgO} \)[/tex], we need to ensure that the number of atoms of each element on the reactant side is equal to the number of atoms on the product side.
Let's breakdown the equation and balance it step-by-step:
1. Unbalanced equation:
[tex]\[ \text{Mg} + \text{O}_2 \rightarrow \text{MgO} \][/tex]
2. Count the number of atoms of each element on both sides:
- Reactants side:
- Mg: 1
- O: 2
- Products side:
- Mg: 1
- O: 1
Notice that the number of oxygen atoms is not balanced. There are 2 oxygen atoms on the reactants side (in [tex]\( \text{O}_2 \)[/tex]) and only 1 oxygen atom on the product side (in [tex]\( \text{MgO} \)[/tex]).
3. Balance the oxygen atoms:
- Since there are 2 oxygen atoms on the reactants side, we need 2 oxygen atoms on the product side. So, we put a coefficient of 2 in front of [tex]\( \text{MgO} \)[/tex]:
[tex]\[ \text{Mg} + \text{O}_2 \rightarrow 2 \text{MgO} \][/tex]
4. Count the atoms again after balancing oxygen:
- Reactants side:
- Mg: 1
- O: 2
- Products side:
- Mg: 2 (Because of the coefficient 2 in front of [tex]\( \text{MgO} \)[/tex])
- O: 2
Now, the oxygen atoms are balanced, but the magnesium atoms are not. We have 1 Mg atom on the reactants side and 2 Mg atoms on the product side.
5. Balance the magnesium atoms:
- To balance the magnesium atoms, we put a coefficient of 2 in front of [tex]\( \text{Mg} \)[/tex] on the reactants side:
[tex]\[ 2 \text{Mg} + \text{O}_2 \rightarrow 2 \text{MgO} \][/tex]
6. Final check:
- Reactants side:
- Mg: 2
- O: 2
- Products side:
- Mg: 2
- O: 2
Now both magnesium and oxygen atoms are balanced on both sides of the equation. Thus, the balanced chemical equation is:
[tex]\[ 2 \text{Mg} + \text{O}_2 \rightarrow 2 \text{MgO} \][/tex]
So the correctly balanced equation is [tex]\( 2 \text{Mg} + \text{O}_2 \rightarrow 2 \text{MgO} \)[/tex].
The correct choice is:
[tex]\[ 2 \text{Mg} + \text{O}_2 \rightarrow 2 \text{MgO} \][/tex]
