To determine which of the given equations is correctly balanced, we need to ensure that the number of atoms of each element on the reactants side (left) is equal to the number of atoms on the products side (right). Let's consider each equation step by step:
Option A: [tex]\( NaClO_3 \rightarrow NaCl + 3 O_2 \)[/tex]
- Reactants side:
- [tex]\( \text{Na} = 1 \)[/tex]
- [tex]\( \text{Cl} = 1 \)[/tex]
- [tex]\( \text{O} = 3 \)[/tex]
- Products side:
- [tex]\( \text{Na} = 1 \)[/tex]
- [tex]\( \text{Cl} = 1 \)[/tex]
- [tex]\( \text{O} = 3 \times 2 = 6 \)[/tex]
This equation is not balanced; oxygen atoms are not equal.
Option B: [tex]\( 2 HgO \rightarrow 2 Hg + O_2 \)[/tex]
- Reactants side:
- [tex]\( \text{Hg} = 2 \)[/tex]
- [tex]\( \text{O} = 2 \)[/tex]
- Products side:
- [tex]\( \text{Hg} = 2 \)[/tex]
- [tex]\( \text{O} = 2 \)[/tex]
This equation is balanced; both mercury and oxygen atoms are equal.
Option C: [tex]\( 2 ZnS + O_2 \rightarrow 2 ZnO + 2 SO_2 \)[/tex]
- Reactants side:
- [tex]\( \text{Zn} = 2 \)[/tex]
- [tex]\( \text{S} = 2 \)[/tex]
- [tex]\( \text{O} = 2 \)[/tex]
- Products side:
- [tex]\( \text{Zn} = 2 \)[/tex]
- [tex]\( \text{S} = 2 \)[/tex]
- [tex]\( \text{O} = 2+2 \times 2 = 6 \)[/tex]
This equation is not balanced; oxygen atoms are not equal.
Option D: [tex]\( 4 CO + Fe_3O_4 \rightarrow 4 CO_2 + Fe \)[/tex]
- Reactants side:
- [tex]\( \text{C} = 4 \)[/tex]
- [tex]\( \text{O} = 4 + 1 \times 4 = 8 \)[/tex]
- [tex]\( \text{Fe} = 3 \)[/tex]
- Products side:
- [tex]\( \text{C} = 4 \)[/tex]
- [tex]\( \text{O} = 4 \times 2 = 8 \)[/tex]
- [tex]\( \text{Fe} = 1 \)[/tex]
This equation is not balanced; iron atoms are not equal.
Option E: [tex]\( 2 Fe + 2 Cl_2 \rightarrow 2 FeCl_3 \)[/tex]
- Reactants side:
- [tex]\( \text{Fe} = 2 \)[/tex]
- [tex]\( \text{Cl} = 2 \times 2 = 4 \)[/tex]
- Products side:
- [tex]\( \text{Fe} = 2 \)[/tex]
- [tex]\( \text{Cl} = 2 \times 3 = 6 \)[/tex]
This equation is not balanced; chlorine atoms are not equal.
Since Option B is the only equation where the number of atoms of each element on the reactants side is equal to the number of atoms of each element on the products side, the correct answer is:
B. [tex]\( 2 HgO \rightarrow 2 Hg + O_2 \)[/tex]
