Respuesta :

Answer is: 117.58 kJ of heat is released when oxygen react.
Chemical reaction: C₂H₄ + 3O₂ → 2CO₂ + 2H₂O; ΔH = +1411 kJ.
m(O₂) = 8.00 g.
n(O₂) = m(O₂) ÷ M(O₂).
n(O₂) = 8 g ÷ 32 g/mol.
n(O₂) = 0.25 mol.
Make proportion: 3mol(O₂) : 1411 kJ = 0.25 mol : Q.
Q = 1411 kJ · 0.25 mol ÷ 3 mol.
Q = 117.58 kJ.