in which chemical equation is the number of atoms in the reactants the same as the number of atoms in the products?

ch4 + o2 -> co2 + 2h2o

1 answer

To determine if the chemical equation \( \text{CH}_4 + \text{O}_2 \rightarrow \text{CO}_2 + 2\text{H}_2\text{O} \) is balanced, we need to count the number of each type of atom on both sides (reactants and products).

Reactants:

  • For \( \text{CH}_4 \) (methane):

    • 1 Carbon (C)
    • 4 Hydrogen (H)
  • For \( \text{O}_2 \) (oxygen):

    • 2 Oxygen (O)

Total in reactants:

  • Carbon: 1
  • Hydrogen: 4
  • Oxygen: 2

Products:

  • For \( \text{CO}_2 \) (carbon dioxide):

    • 1 Carbon (C)
    • 2 Oxygen (O)
  • For \( 2\text{H}_2\text{O} \) (water):

    • 4 Hydrogen (H)
    • 2 Oxygen (O)

Total in products:

  • Carbon: 1
  • Hydrogen: 4
  • Oxygen: 4 (2 from \( \text{CO}_2 \) and 2 from \( 2\text{H}_2\text{O} \))

Summary of counts:

  • Reactants:
    • C: 1, H: 4, O: 2
  • Products:
    • C: 1, H: 4, O: 4

The number of atoms of Carbon and Hydrogen is the same on both sides, but the number of Oxygen atoms is not the same (2 in reactants vs. 4 in products).

Therefore, the equation is not balanced.

To balance the equation, the correct form would be:

\[ \text{CH}_4 + 2\text{O}_2 \rightarrow \text{CO}_2 + 2\text{H}_2\text{O} \]

This way, we would have:

  • Reactants: C: 1, H: 4, O: 4
  • Products: C: 1, H: 4, O: 4

Now, the number of atoms in the reactants equals the number of atoms in the products.