Enthalpy Stoichiometry

For PCl₃(g) + Cl₂(g) → PCl₅(g)   ΔH = −87.9 kJ, how much energy is released per mole of PCl₅ formed?

How many kilojoules are given off when 17.8 mol of CH₄ react? CH₄(g) + 2O₂(g) → CO₂(g) + 2H₂O(ℓ)   ΔH = −890.1 kJ

How many kilojoules are absorbed when 23.09 mol of C₆H₆ are formed? 6C(s) + 3H₂(g) → C₆H₆(ℓ)   ΔH = +49.0 kJ
energy absorbed = 1($) kJ

How much energy is given off when 100.0 g of C₆H₁₂O₆ react? C₆H₁₂O₆ + 6O₂ → 6CO₂ + 6H₂O   ΔH = −2799 kJ

How much energy is absorbed when 85.2 g of CO₂ react? 2CO₂(g) → 2CO(g) + O₂(g)   ΔH = 566 kJ

What mass of NaHCO₃ is decomposed by 256 kJ? 2NaHCO₃(s) → Na₂CO₃(s) + CO₂(g) + H₂O(ℓ)   ΔH = 91.5 kJ

What mass of SO₃ is needed to generate 1,566 kJ? Fe₂O₃(s) + 3SO₃(g) → Fe₂(SO₄)₃(s)   ΔH = −570.2 kJ