To determine which chemical equation has the same number of atoms on each side (reactants and products), we need to count the atoms for each of the provided equations.
-
CO2 + H2O → CH2OH + O2
-
Reactants:
- C: 1 (from CO2)
- O: 3 (2 from CO2 and 1 from H2O)
- H: 2 (from H2O)
-
Total = 1 C + 3 O + 2 H = 6 atoms
-
Products:
- C: 1 (from CH2OH)
- O: 3 (1 from CH2OH and 2 from O2)
- H: 2 (from CH2OH)
-
Total = 1 C + 3 O + 2 H = 6 atoms
This equation is balanced.
-
-
Zn + 2HCl → H2 + ZnCl2
-
Reactants:
- Zn: 1
- H: 2 (from 2 HCl)
- Cl: 2 (from 2 HCl)
-
Total = 1 Zn + 2 H + 2 Cl = 5 atoms
-
Products:
- H: 2 (from H2)
- Zn: 1 (from ZnCl2)
- Cl: 2 (from ZnCl2)
-
Total = 2 H + 1 Zn + 2 Cl = 5 atoms
This equation is balanced.
-
-
Li2CO3 → LiO + CO2
-
Reactants:
- Li: 2 (from Li2CO3)
- C: 1 (from Li2CO3)
- O: 3 (from Li2CO3)
-
Total = 2 Li + 1 C + 3 O = 6 atoms
-
Products:
- Li: 1 (from LiO)
- O: 1 (from LiO)
- C: 1 (from CO2)
- O: 2 (from CO2)
-
Total = 1 Li + 1 C + 3 O = 5 atoms
This equation is not balanced.
-
-
CH4 + O2 → CO2 + 2H2O
-
Reactants:
- C: 1 (from CH4)
- H: 4 (from CH4)
- O: 2 (from O2)
-
Total = 1 C + 4 H + 2 O = 7 atoms
-
Products:
- C: 1 (from CO2)
- H: 4 (from 2 H2O)
- O: 3 (2 from 2 H2O and 1 from CO2)
-
Total = 1 C + 4 H + 3 O = 8 atoms
This equation is not balanced.
-
From this analysis, the first and second equations (CO2 + H2O → CH2OH + O2 and Zn + 2HCl → H2 + ZnCl2) are the only balanced equations, with the same number of atoms on both sides.
So the answer is:
- CO2 + H2O → CH2OH + O2
- Zn + 2HCl → H2 + ZnCl2
Since only one choice can be selected based on the question format, you can choose either of these two as they both satisfy the condition. However, for official responses, the first listed is often accepted.