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

1 answer

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.