To determine which chemical equation has the same number of atoms in the reactants as in the products, we need to count the total number of atoms for each equation provided.
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Li2CO3 → LiO + CO2
- Reactants: 2 Li + 1 C + 3 O = 6 atoms
- Products: 1 Li + 1 O + 1 C + 2 O = 4 atoms
- Not balanced (6 ≠ 4)
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CO2 + H2O → CH2OH + O2
- Reactants: 1 C + 2 O (from CO2) + 2 H + 1 O (from H2O) = 5 atoms
- Products: 1 C + 2 H + 1 O + 2 O = 6 atoms
- Not balanced (5 ≠ 6)
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CH4 + O2 → CO2 + 2H2O
- Reactants: 1 C + 4 H + 2 O = 7 atoms
- Products: 1 C + 2 O + 4 H = 7 atoms
- Balanced (7 = 7)
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Zn + 2HCl → H2 + ZnCl2
- Reactants: 1 Zn + 2 H + 2 Cl = 5 atoms
- Products: 1 Zn + 2 H + 2 Cl = 5 atoms
- Balanced (5 = 5)
From the analysis, both the third equation (CH4 + O2 → CO2 + 2H2O) and the fourth equation (Zn + 2HCl → H2 + ZnCl2) have the same number of atoms in the reactants and products.
However, since the question typically asks for a single answer, if we choose the first equation that shows balance clearly:
Answer: CH4 + O2 → CO2 + 2H2O (3rd option)