Final answer:
Out of the given equations, Equations A (2H2 + O2 → 2H2O), C (4Fe + 3O2 → 2Fe2O3), and D (N2 + 3H2 → 2NH3) are balanced, while Equation B (CH4 + O2 → CO2 + H2O) is not balanced unless revised to include the proper coefficients.
Step-by-step explanation:
The balanced equations are:
A) 2H₂ + O₂ → 2H₂O
B) CH₄ + 2O₂ → CO₂ + 2H₂O
D) N₂ + 3H₂ → 2NH₃
In equation A, both the number of hydrogen (H) and oxygen (O) atoms are balanced. In equation B, the carbon (C) and hydrogen (H) atoms are balanced, as well as the oxygen (O) atoms on each side. In equation D, the nitrogen (N) and hydrogen (H) atoms are balanced. Therefore, these equations are balanced.
To determine if a chemical equation is balanced, one must ensure that the number of atoms of each element is the same on both sides of the equation. In the examples provided, let us examine each equation:
- Equation A: 2H₂ + O₂ → 2H₂O is correctly balanced with 4 hydrogen atoms and 2 oxygen atoms on both sides.
- Equation B: CH₄ + O₂ → CO₂ + H₂O is not balanced as written. It would need to be written as CH₄ + 2O₂ → CO₂ + 2H₂O to be balanced.
- Equation C: 4Fe + 3O₂ → 2Fe₂O₃ is balanced with 4 iron atoms and 6 oxygen atoms on both sides.
- Equation D: N₂ + 3H₂ → 2NH₃ is also balanced with 2 nitrogen atoms and 6 hydrogen atoms on both sides.
Therefore, Equations A, C, and D are balanced, whereas Equation B is not balanced unless adjusted with the correct coefficients.