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vampirchik [111]

3 years ago

15

When 1 mole of H2(g) reacts with F2(g) to form HF(g) according to the following equation, 542 kJ of energy are evolved H2(g) + F

2(g2HF(g) Is this reaction endothermic or exothermic? What is the value of q? kJ When 1 mole of Fe203(s) reacts with H2(g) to form Fe(s) and H20(g) according to the following equation, 98.8 kJ of energy are absorbed Fe2O3(s) +3H2(g)^2Fe(s) + 3H2Og) Is this reaction endothermic or exothermic? What is the value of q? kJ

1 answer:

d1i1m1o1n [39]3 years ago

6 0

Answer:

Exothermic. q = -542 kJ

Endothermic. q = 98.8 kJ

Explanation:

<em>When 1 mole of H₂(g) reacts with F₂(g) to form HF(g) according to the following equation, 542 kJ of energy are evolved. </em>

<em>H₂(g) + F₂(g) ⇄ 2 HF(g) </em>

<em>Is this reaction endothermic or exothermic? What is the value of q?</em>

Since the heat is evolved, the reaction is exothermic. When the reaction is exothermic, q is negative, that is, q = -542 kJ.

<em>When 1 mole of Fe₂O₃(s) reacts with H₂(g) to form Fe(s) and H₂0(g) according to the following equation, 98.8 kJ of energy are absorbed</em>

<em>Fe₂O₃(s) + 3 H₂(g) ⇄ 2 Fe(s) + 3 H₂O(g) </em>

<em>Is this reaction endothermic or exothermic? What is the value of q?</em>

Since the heat is absorbed, the reaction is endothermic. When the reaction is endothermic, q is positive, that is, q = 98.8 kJ.

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In the given question, we need to express the van der Waals equation of state as a virial expansion in powers of 1/Vm and obtain expressions for B and C in terms of the parameters a and b. Therefore:

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