sulide occurs via the following reaction 6 (24 points) The decomposition of hydr

Question

sulide occurs via the following reaction 6 (24 points) The decomposition of hydrogen At a temperature of 1065 C, this reaction doecs not go to completion of H,S is put into a 50o.0-mL. reaction vessel at a temperature of 108S c of the H,S decomes. The volume of the reaction vessel is held constant during the reaction °C, only 24.0% a. How many moles of H,S are present before the reaction occurs? b. Calculate the partial pressure of each gaseous species in the final reaction mix- ture. c. What is the total pressure of the reaction mixture? d. If we were to put the vessel containing the final reaction mixture in a vacuunm and poke a hole in the side of the box, which species would escape from the vessel first? e. If we were to put the vessel containing the final reaction mixture in a classroom and open the vessel, which species would move the farthest in 10 minutes? What information would we need to know to calculate E for the reaction? Page 8

Explanation / Answer

a)

mol of H2S before reaction

PV = nRT

n = PV/(RT)

n = (1)(0.5)/(0.082*(1065+273))

n = 0.004557 moles of H2S

b)

Pgas after mix:

2 mol of H2S = 2 mol of H2, 1 mol of S2

0.004557 mol of H2S = 0.004557 mol of H2

0.004557 mol of H2S = 1/2*0.004557 = 0.0022785 mol of S2

this is at 100%, at 24%| expect:

mol of H2 formed = 0.004557 *24/100 = 0.00109368

mol of S2 formed = 0.0022785  *24/100 = 0.00054684

mol of H2S left = 0.004557 - 0.00109368 = 0.00346332

total mol = 0.00109368+0.00054684+0.00346332 = 0.00510384

mol fractions

x-H2S = 0.00346332/0.00510384 = 0.6785

x-S2 = 0.00054684/0.00510384 = 0.10714

x-H2 = 0.00109368/0.00510384 = 0.21428

Pnew:

P1/n1 = P2/n2

1/0.004557 = P2/0.00510384

P2 = 0.00510384 /0.004557 = 1.12 atm

P-x= mol frac. X * Ptotal

P-H2S = 0.6785*1.12 = 0.75992 atm

P-S2 = 0.10714*1.12 = 0.1199 atm

P-H2 = 0.21428*1.12 = 0.23999 atm

c)

total P, as stated above = 1.12 atm

d)

species wih highest Pressure escapes first --> H2S  

e)

farthest in 10 min, will be the lightest, due to effusion

f.

dE = Q - W

heat of reaction required, Work = 0 , since no change in volume

Related Questions

Navigate

• Browse (All)
• Browse S
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.