Heterogenous equilibrium of ammonium
bisulfide. Ammonium bisulfide NH4HS forms ammonia NH3 and hydrogen sulfide H2S through the reaction NH4HS(s) arrows + H2S(g). This reaction has a kp value of 0.120 at 25 C. A 5.0-L flask is charged with .400g of pure H2S(g) at 25 C.
Evaluate the validity of the following statement. Give true or false anwswers and please explain so I can understand. I thought I did, but my answers are wrong:
No reaction occurs?
The reaction proceeds to the left?
The reaction proceeds to the right?
Q is greater than K?
Q is equal to 0?
The pressure of ammonia is zero?
What is the initial pressure of H2S(g) in the flask? Express answer numerically in atmospheres.
p = ________________atm
You need to explain the problem a little better. Is that the NH4HS system in equilibrium at 25C and the 5.00 L flask is charged with enough H2S to make 0.4 kg H2S? Or is that an additional 0.4 kg H2S is added to the equilibrium mixture? The way the sentence is structured says that you are placing 0.4 g H2S is a 5.00 L flask. Of course, no NH4HS can come out of that.
Initial pressure H2S is
moles H2S = 0.4/molar mass H2S.
Use PV = nRT and solve for partial pressure of H2S.
To evaluate the validity of the statements, let's first determine the initial pressure of H2S(g) in the flask.
The initial pressure of H2S(g) can be found using the ideal gas law equation:
PV = nRT
where P is the pressure, V is the volume, n is the number of moles, R is the ideal gas constant, and T is the temperature.
First, we need to convert the mass of H2S(g) to moles. The molar mass of H2S is 34.08 g/mol.
moles of H2S = mass of H2S / molar mass of H2S
moles of H2S = 0.400 g / 34.08 g/mol
moles of H2S ≈ 0.0117 mol
Now, we can substitute the values into the ideal gas law equation:
P * 5.0 L = (0.0117 mol) * 0.0821 L·atm/(mol·K) * 298 K
Solving for P gives us:
P ≈ (0.0117 mol * 0.0821 L·atm/(mol·K) * 298 K) / 5.0 L
P ≈ 0.0733 atm
Therefore, the initial pressure of H2S(g) in the flask is approximately 0.0733 atm.
Now let's evaluate the validity of the statements:
1. No reaction occurs? (False)
Since H2S(g) is present in the flask, a reaction can occur.
2. The reaction proceeds to the left? (False)
The reaction is written as NH4HS(s) ↔ NH3(g) + H2S(g). The double arrows indicate an equilibrium reaction, meaning the reaction can occur in both directions. It is not biased towards any particular direction.
3. The reaction proceeds to the right? (True)
The reaction can occur in both directions, so it can proceed to the right, forming NH3(g) and H2S(g).
4. Q is greater than K? (False)
Q is the reaction quotient, which is calculated similarly to K but using the initial concentrations or pressures instead of equilibrium values. Since we have not yet calculated the concentrations or pressures of NH3 and H2S, we cannot compare Q and K.
5. Q is equal to 0? (False)
As mentioned above, we cannot calculate Q without knowing the concentrations or pressures of NH3 and H2S.
6. The pressure of ammonia is zero? (True)
The flask is initially charged with H2S only, so there is no initial pressure or concentration of NH3.
To summarize:
No reaction occurs? (False)
The reaction proceeds to the left? (False)
The reaction proceeds to the right? (True)
Q is greater than K? (False)
Q is equal to 0? (False)
The pressure of ammonia is zero? (True)
The initial pressure of H2S(g) in the flask is approximately 0.0733 atm.