Oh my my test is coming up and I have no idea how to do these questions and when I asked my teacher for help he said you should do it yourself.... Thanks!

An intermediate step in the production of battery acid, sulfuric acid, invoves the information of sulfur trioxide gas from sulfur dioxide and oxygen gases. (this reaction is also the usual first step in the production of acid rain).

The Kp for this reaction at 830degreeC is 0.13. In one experiment, 96.9g of sufur dioxide and 34.6g of oxygen were added to a rxn flask. What must the total pressure in the flask be at eqilibrium if the reaction has an 80% yield of sulfur trioxide. Assume the volume is 3.5L.

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Consider the rxn; 4A + B <---> 3C. Initially we had 12 mol of A 12 mol of B in a 2.00L flask, At equilibrium, there is 7.5mol of C in the flask.

Find K and % completion?

As I see the the first problem.

2SO2 + O2 ==> 2SO3.
Convert g SO2 to mols, convert that to mols SO3, take 80%. That is mols SO3 we should have at the end of the reaction for an 80% yield. Then calculate SO2 remaining, O2 used up (at 80%) and O2 remaining. Add mols of each and use PV = nRT to determine total P.
Check my thinking.

For the second problem, I posted once and it came out garbled so I erased it and started over. Use the ICE chart to solve this. I can't make a good one on the board but hopefully you can understand what I've written.

4A + B ==> 3C

I = initial concentrations:
for A: 12.0 mols/2.00 L = 6.00 M
for B: 12.0 mols/2.00 L = 6.00 M
for C: o mols/2.00 L = 0 M

C = change:
do this last but I will do the equilibrium and explain what goes in these blanks. You must do change to obtain E.

E = equilibrium:
The problem states we had 7.5 mols C at equilibrium. 7.5 mols/2.00 L = 3.50M goes here which means the change for C must be +3.75; i.e., 0 + 3.75 = 3.75.
If we had +3.75 for change of C, then B must be changed by -3.75/3 = -1.25 M and the final E for compound B is 6.00 - 1.25 = 4.75.
For A: The change for B was -1.25; therefore, the change for A must be 4 x -1.25 = 5.00 which makes E for compound A 6.00 - 5.00 = 1.00.
Now just plug all of those equilibrium numbers into the expression for K and solve for K.

Note I had a typo:

E = equilibrium:
The problem states we had 7.5 mols C at equilibrium. 7.5 mols/2.00 L = 3.50M SHOULD BE 3.75 M goes here which means the change for C must be +3.75; i.e., 0 + 3.75 = 3.75.

Everything was good until this happened:

An intermediate step in the production of battery acid, sulfuric acid, invoves the information of sulfur trioxide gas from sulfur dioxide and oxygen gases. (this reaction is also the usual first step in the production of acid rain).

The Kp for this reaction at 830degreeC is 0.13. In one experiment, 96.9g of sufur dioxide and 34.6g of oxygen were added to a rxn flask. What must the total pressure in the flask be at eqilibrium if the reaction has an 80% yield of sulfur trioxide. Assume the volume is 3.5L.

As I see the the first problem.
2SO2 + O2 ==> 2SO3.
Convert g SO2 to mols, convert that to mols SO3, take 80%. That is mols SO3 we should have at the end of the reaction for an 80% yield. Then calculate SO2 remaining, O2 used up (at 80%) and O2 remaining. Add mols of each and use PV = nRT to determine total P.
Check my thinking.

To solve the first problem, we need to use the concept of equilibrium constants (Kp) and the stoichiometry of the reaction. Here's a step-by-step guide to finding the total pressure in the flask:

Step 1: Write the balanced chemical equation:
SO2(g) + 0.5O2(g) ⇄ SO3(g)

Step 2: Calculate the moles of each reactant:
Moles of SO2 = mass / molar mass = 96.9 g / (32.06 g/mol) = 3.02 mol
Moles of O2 = mass / molar mass = 34.6 g / (32.00 g/mol) = 1.08 mol

Step 3: Use the balanced equation to determine the moles of sulfur trioxide formed:
From the balanced equation, we can see that the stoichiometry between SO2 and SO3 is 1:1.
Since the percentage yield is given as 80%, the moles of SO3 produced = 0.8 * 3.02 mol = 2.42 mol

Step 4: Calculate the total number of moles at equilibrium:
Moles of SO2 remaining = 3.02 - 2.42 = 0.60 mol
Moles of O2 remaining = 1.08 - 0.54 = 0.54 mol
Moles of SO3 = 2.42 mol

Step 5: Calculate the partial pressures of each gas using the ideal gas law:
P = (n * R * T) / V, where P is the pressure, n is the number of moles, R is the ideal gas constant, T is the temperature in Kelvin, and V is the volume.

At 830°C, T = 830 + 273 = 1103 K
R = 0.0821 L·atm/(mol·K)

Partial pressure of SO2 = (0.60 mol * 0.0821 L·atm/(mol·K) * 1103 K) / 3.5 L
Partial pressure of O2 = (0.54 mol * 0.0821 L·atm/(mol·K) * 1103 K) / 3.5 L
Partial pressure of SO3 = (2.42 mol * 0.0821 L·atm/(mol·K) * 1103 K) / 3.5 L

Step 6: Calculate the total pressure at equilibrium:
Total pressure = Partial pressure of SO2 + Partial pressure of O2 + Partial pressure of SO3

I hope this step-by-step guide helps you understand how to approach this problem and solve it on your own. Good luck with your test!

For the second problem, we need to find the equilibrium constant (K) and the percentage completion of the reaction. Here's how you can do it:

Step 1: Write the balanced chemical equation:
4A + B ⇄ 3C

Step 2: Identify the initial and equilibrium moles of each species:
Initial moles:
A = 12 mol
B = 12 mol
C = 0 mol

Equilibrium moles:
A = 12 mol - x (assuming x mol of A reacts)
B = 12 mol - x (assuming x mol of B reacts)
C = 3 * x (according to the stoichiometry)

Step 3: Set up the expression for the equilibrium constant (K):
K = ([C]^3) / ([A]^4[B])

Step 4: Substitute the equilibrium concentrations into the equilibrium constant expression:
K = (3 * x)^3 / (12 - x)^4 * (12 - x)

Step 5: Solve for x:
Given that there are 7.5 mol of C at equilibrium, set up the equation:
7.5 = 3 * x
Solving for x, you'll find that x = 2.5 mol

Step 6: Substitute the value of x into the equilibrium expression to find K:
K = (3 * 2.5)^3 / (12 - 2.5)^4 * (12 - 2.5)

Step 7: Calculate the percentage completion of the reaction:
% Completion = (moles reacted / initial moles) * 100
% Completion = (2.5 mol / 12 mol) * 100

I hope this explanation helps you understand how to approach these types of problems. Remember to always understand the concepts behind the equations so you can apply them correctly. Good luck on your test!