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 CO 2 + H 2 O → CH 2 OH + O 2 CH4 + O2 → CO2 + 2H2O CH 4 + O 2 → CO 2 + 2H 2 O Zn + 2HCl → H2 + ZnCl2 Zn + 2HCl → H 2 + ZnCl 2 Li2CO3 → LiO + CO2

Answer 1

To determine which chemical equation has the same number of atoms in the reactants as in the products, we need to balance each equation.

1. \( \text{CO}_2 + \text{H}_2\text{O} \rightarrow \text{CH}_2\text{OH} + \text{O}_2 \)

- Reactants: 1 C, 2 O (from CO2), 2 H (from H2O) → Total: 1 C, 4 O, 2 H
- Products: 1 C (from CH2OH), 2 H (from CH2OH), 2 O (1 from CH2OH, 1 from O2) → Total: 1 C, 2 H, 2 O
- **Not balanced.**

2. \( \text{CO}_2 + \text{H}_2\text{O} \rightarrow \text{CH}_2\text{OH} + \text{O}_2 \) (same as above, reformatted)

- Same as above, **not balanced.**

3. \( \text{CH}_4 + \text{O}_2 \rightarrow \text{CO}_2 + 2\text{H}_2\text{O} \)

- Reactants: 1 C (from CH4), 4 H (from CH4), 2 O (from O2) → Total: 1 C, 2 O, 4 H
- Products: 1 C (from CO2), 4 H (from 2 H2O), 3 O (1 from CO2, 2 from H2O) → Total: 1 C, 4 H, 3 O
- **Not balanced.**

4. \( \text{CH}_4 + \text{O}_2 \rightarrow \text{CO}_2 + 2\text{H}_2\text{O} \) (same as above)

- Same as above, **not balanced.**

5. \( \text{Zn} + 2\text{HCl} \rightarrow \text{H}_2 + \text{ZnCl}_2 \)

- Reactants: 1 Zn, 2 H, 2 Cl → Total: 1 Zn, 2 H, 2 Cl
- Products: 1 Zn, 2 H (from H2), 2 Cl (from ZnCl2) → Total: 1 Zn, 2 H, 2 Cl
- **Balanced!**

6. \( \text{Li}_2\text{CO}_3 \rightarrow \text{LiO} + \text{CO}_2 \)

- Reactants: 2 Li, 1 C, 3 O → Total: 2 Li, 1 C, 3 O
- Products: 1 Li (from LiO), 1 O (from LiO), 1 C (from CO2), 2 O (from CO2) → Total: 1 Li, 1 C, 3 O
- **Not balanced.**

The balanced equation, where the number of atoms in the reactants equals the number of atoms in the products, is:

**Zn + 2HCl → H2 + ZnCl2**.