To determine which of the given chemical equations is correctly balanced, we need to ensure that the number of atoms of each element on the reactant side is equal to the number of atoms of that element on the product side.
Let's go through each option one by one:
### Option A: [tex]\( \text{NaClO}_3 \rightarrow \text{NaCl} + 3 \text{O}_2 \)[/tex]
- Reactants: 1 Na, 1 Cl, 3 O
- Products: 1 Na, 1 Cl, 6 O
This equation is not balanced because the number of oxygen atoms does not match. Hence, Option A is incorrect.
### Option B: [tex]\( 2 \text{HgO} \rightarrow 2 \text{Hg} + \text{O}_2 \)[/tex]
- Reactants: 2 Hg, 2 O
- Products: 2 Hg, 2 O
This equation is balanced because the number of Hg and O atoms on both sides are equal. Hence, Option B is correct.
### Option C: [tex]\( 2 \text{ZnS} + \text{O}_2 \rightarrow 2 \text{ZnO} + 2 \text{SO}_2 \)[/tex]
- Reactants: 2 Zn, 2 S, 2 O
- Products: 2 Zn, 2 S, 4 O
This equation is not balanced because the number of oxygen atoms does not match (2 O atoms on the reactant side vs. 4 O atoms on the product side). Hence, Option C is incorrect.
### Option D: [tex]\( 4 \text{CO} + \text{Fe}_3\text{O}_4 \rightarrow 4 \text{CO}_2 + \text{Fe} \)[/tex]
- Reactants: 4 C, 4 O, 3 Fe O
- Products: 4 C, 8 O, 1 Fe
This equation is not balanced because the number of Fe and O atoms do not match. Hence, Option D is incorrect.
### Option E: [tex]\( 2 \text{Fe} + 2 \text{Cl}_2 \rightarrow 2 \text{FeCl}_3 \)[/tex]
- Reactants: 2 Fe, 4 Cl
- Products: 2 Fe, 6 Cl
This equation is not balanced because the number of chlorine atoms does not match (4 Cl atoms on the reactant side vs. 6 Cl atoms on the product side). Hence, Option E is incorrect.
### Conclusion
Only Option B, [tex]\( 2 \text{HgO} \rightarrow 2 \text{Hg} + \text{O}_2 \)[/tex], is correctly balanced. Therefore, the correct answer is:
B. [tex]\( 2 \text{HgO} \rightarrow 2 \text{Hg} + \text{O}_2 \)[/tex]
