To determine which of the given chemical equations is correctly balanced, we need to ensure that the number of atoms for each element is the same on both the reactant and the product sides of the equation. Let's examine each equation in detail:
A. [tex]\( NaClO_3 \rightarrow NaCl + 3 O_2 \)[/tex]:
- Reactants: 1 Na, 1 Cl, 3 O
- Products: 1 Na, 1 Cl, 6 O (3 molecules of [tex]\( O_2 \)[/tex] each contain 2 O atoms)
The oxygen atoms are not balanced (3 on the reactant side, 6 on the product side). Thus, this equation is not correctly balanced.
B. [tex]\( 2 HgO \rightarrow 2 Hg + O_2 \)[/tex]:
- Reactants: 2 Hg, 2 O
- Products: 2 Hg, 2 O (since [tex]\( O_2 \)[/tex] contains 2 O atoms)
Both the mercury (Hg) and oxygen (O) atoms are balanced. This equation is correctly balanced.
C. [tex]\( 2 ZnS + O_2 \rightarrow 2 ZnO + 2 SO_2 \)[/tex]:
- Reactants: 2 Zn, 2 S, 2 O
- Products: 2 Zn, 2 S, 4 O (2 from [tex]\( ZnO \)[/tex] and 2 [tex]\( SO_2 \)[/tex])
The oxygen atoms are not balanced (2 on the reactant side, 4 on the product side). Thus, this equation is not correctly balanced.
D. [tex]\( 4 CO + Fe_3O_4 \rightarrow 4 CO_2 + Fe \)[/tex]:
- Reactants: 4 C, 4 O (from CO), and 3 Fe, 4 O (from [tex]\( Fe_3O_4 \)[/tex])
- Products: 4 C, 8 O (from [tex]\( CO_2 \)[/tex]), and 1 Fe
The oxygen and iron atoms are not balanced. Thus, this equation is not correctly balanced.
E. [tex]\( 2 Fe + 2 Cl_2 \rightarrow 2 FeCl_3 \)[/tex]:
- Reactants: 2 Fe, 4 Cl
- Products: 2 Fe, 6 Cl
The chlorine atoms are not balanced (4 on the reactant side, 6 on the product side). Thus, this equation is not correctly balanced.
Therefore, the only correctly balanced equation is:
B. [tex]\( 2 HgO \rightarrow 2 Hg + O_2 \)[/tex]
