Question

In which chemical equation is the number of atoms in the reactants the same as the number of atoms in the products?(1 point)
Responses

CO2 + H2O → CH2OH + O2

CH4 + O2 → CO2 + 2H2O

Li2CO3 → LiO + CO2

Zn + 2HCl → H2 + ZnCl2

Answer 1

To determine which chemical equation has the same number of atoms in the reactants as in the products, we need to count the number of atoms for each element in both the reactants and products of the given equations.

1. **CO2 + H2O → CH2OH + O2**
- Reactants:
- C: 1 (from CO2)
- O: 3 (2 from CO2, 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, 2 from O2)
- H: 2 (from CH2OH)
- Total = 1 C + 3 O + 2 H = 6 atoms

2. **CH4 + O2 → CO2 + 2H2O**
- Reactants:
- C: 1 (from CH4)
- O: 2 (from O2)
- H: 4 (from CH4)
- Total = 1 C + 2 O + 4 H = 7 atoms
- Products:
- C: 1 (from CO2)
- O: 3 (2 from H2O, 1 from CO2)
- H: 4 (from 2H2O)
- Total = 1 C + 3 O + 4 H = 8 atoms

3. **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)
- C: 1 (from CO2)
- O: 3 (from LiO and CO2)
- Total = 1 Li + 1 C + 3 O = 5 atoms

4. **Zn + 2HCl → H2 + ZnCl2**
- Reactants:
- Zn: 1 (from Zn)
- H: 2 (from 2HCl)
- Cl: 2 (from 2HCl)
- Total = 1 Zn + 2 H + 2 Cl = 5 atoms
- Products:
- H: 2 (from H2)
- Zn: 1 (from ZnCl2)
- Cl: 2 (from ZnCl2)
- Total = 1 Zn + 2 H + 2 Cl = 5 atoms

Thus, the only equation where the total number of atoms in the reactants equals the total number of atoms in the products is:

**CO2 + H2O → CH2OH + O2**

This is the correct answer!