In Which of the Reactions Below Is ΔH an Enthalpy

question 22

Multiple Choice

In which of the reactions below is ΔH an enthalpy of formation?

• A) S₈(s)+ 8O₂(g)→ 8SO₂(g)
• B) N₂(g)+ O₂(g)→ 2NO(g)
• C) H₂(g)+ Cl₂(g)+ 4O₂(g)→ 2HClO₄(l)
• D) Cu(s)+ 1/2I₂(s)→ CuI(s)
• E) CH₄(g)+ 2O₂(g)→ CO₂(g)+ 2H₂O(g)