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)

LI₂CO₃LIO + CO2

Zn+2HCl→H₂ + ZnCl2

HOCO₂ + 2H₂O

CO₂H₂OCH₂OH + O2

Answer 1

To determine which chemical equation has the same number of atoms in the reactants as in the products, let's analyze each equation provided:

1. **Li₂CO₃ → LiO + CO₂**
- Reactants:
- 2 Li
- 1 C
- 3 O
- Products:
- 1 Li
- 1 O
- 1 C
- 2 O (from CO₂)
- Total:
- Reactants: 2 + 1 + 3 = 6 atoms
- Products: 1 + 1 + 1 + 2 = 5 atoms

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

3. **HOCO₂ + 2H₂O**
- This appears to be incomplete and lacks a product. I'll assume it is meant to be a balanced equation. We need products to compare.

4. **C₂H₅OH + O₂**
- This is also incomplete without products. Assuming it is intended to indicate combustion which typically produces CO₂ and H₂O.

To summarize:

Analyzing the second equation, **Zn + 2HCl → H₂ + ZnCl₂**, both sides balance perfectly with 5 atoms in total (3 in the reactants: 1 Zn, 2 H, and 2 Cl; and 5 in the products: 2 H and 1 Zn and 2 Cl).

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

**Zn + 2HCl → H₂ + ZnCl₂**.