Which of the following is the correctly balanced chemical equation for the reaction between hydrogen sulfide and oxygen among volcanic gases to produce sulfur dioxide and water?

• A. 2 H2S + 3 O2 → 2 SO2 + 2 H2O
• B. H2S + 2 O2 → SO2 + 2 H2O
• C. H2S + O2 → SO2 + H2O
• D. 2 H2S + O2 → 2 SO2 + 2 H2O

Answer: (A)

Verified step by step guidance

1. Identify the reactants and products in the chemical reaction. Here, hydrogen sulfide (H2S) reacts with oxygen (O2) to produce sulfur dioxide (SO2) and water (H2O).
2. Write the unbalanced chemical equation: \(\mathrm{H_2S + O_2 \rightarrow SO_2 + H_2O}\).
3. Balance the atoms of each element one at a time, starting with sulfur (S). Since there is 1 sulfur atom in H2S and 1 in SO2, balance sulfur by placing coefficients accordingly.
4. Next, balance hydrogen (H) atoms. There are 2 hydrogens in H2S and 2 hydrogens in H2O, so adjust coefficients to have equal numbers on both sides.
5. Finally, balance oxygen (O) atoms. Count the total oxygen atoms on the product side and adjust the coefficient of O2 on the reactant side to balance the oxygen atoms, ensuring all coefficients are the smallest whole numbers.