Which of the following chemical equations is correctly balanced?

• A. 2K + O_2 ightarrow 2K_2O
• B. H_2 + O_2 ightarrow H_2O_2
• C. 2Na + Cl_2 ightarrow 2NaCl
• D. H_2 + O_2 ightarrow H_2O

Answer: (C)

Verified step by step guidance

1. Identify the number of atoms of each element on both sides of each chemical equation to check if they are balanced.
2. For the equation \$2K + O_2 \rightarrow 2K_2O$, count potassium (K) and oxygen (O) atoms on both sides: reactants have 2 K and 2 O atoms, products have 4 K and 2 O atoms, so it is not balanced.
3. For the equation \(H_2 + O_2 \rightarrow H_2O_2\), count hydrogen (H) and oxygen (O) atoms: reactants have 2 H and 2 O atoms, products have 2 H and 2 O atoms, so it is balanced.
4. For the equation \$2Na + Cl_2 \rightarrow 2NaCl$, count sodium (Na) and chlorine (Cl) atoms: reactants have 2 Na and 2 Cl atoms, products have 2 Na and 2 Cl atoms, so it is balanced.
5. For the equation \(H_2 + O_2 \rightarrow H_2O\), count hydrogen and oxygen atoms: reactants have 2 H and 2 O atoms, products have 2 H and 1 O atom, so it is not balanced.