contestada

Consider the following data: S(s) + O2(g) → SO2(g)    ΔHrxn = -297 kJ 2SO3(g) → 2SO2(g) + O2(g)  ΔHrxn = 198 kJ Use Hess's law to determine ^Hrxn for this reaction: 2S(s) + 3O2(g) ---> 2SO3(g) ^Hrxn = ?

Respuesta :

superman1987

Answer: -792 KJ.

Explanation:

  • To get ΔH of the reaction: 2S + 3O₂ → 2SO₃
  • The sum of the two mentioned equations should give the result of the reaction we need to calculate its ΔH.
  • We multiply the first equation by 2 and also its ΔHrxn:

2S + 2O₂ → 2SO₂             ΔHrxn = -594 KJ

  • and reverse the second reaction and so, multiply the ΔHrxn by -1:

2SO₂ + O₂ → 2SO₃          ΔHrxn = -198 KJ

  • By summing the two reactions, we get the reaction that we need to calculate its ΔHrxn: 2S + 3O₂ → 2SO₃
  • Now, we can apply Hess's law says that ΔH is a state function that do not depend on the path of the reaction but depends on the initial and final state.
  • ΔHrxn = ΔH of the first reaction + ΔH of the second reaction
  • ΔHrxn = (-594 KJ) + (-198 KJ) = -792 KJ.
mickymike92

Based on the data provided, ΔHrxn for the reaction 2S + 3O₂ → 2SO₃ is -792 KJ.

What is Hess law of constant heat summation?

Hess law of constant heat summation states the entjalpy ΔH is a state function which independent of the path of the reaction but depends on the initial and final state.

To determine ΔHrxn of the reaction: 2S + 3O₂ → 2SO₃;

We multiply the first equation by 2

  • 2S + 2O₂ → 2SO₂  ΔHrxn = -594 KJ

The second equation is reversed to give:

  • 2SO₂ + O₂ → 2SO₃ ΔHrxn = -198 KJ

Summing the two reactions gives the reaction below:

  • 2S + 3O₂ → 2SO₃

Then, summation of the ΔH of the first and second reactions gives ΔHrxn:

ΔHrxn = (-594 KJ) + (-198 KJ)

ΔHrxn = -792 KJ

Therefore, the ΔHrxn for the reaction 2S + 3O₂ → 2SO₃ is -792 KJ.

Learn more about Hess' law at: https://brainly.com/question/9328637

Otras preguntas