Dr.Bob222 please help
given the following table of thermodynamic data
substance delta HofF S
PCl3 -288.07 kJ/mol 311.7 J/mol-k PCl3 -319.6 kJ/mol 217 J/mol- k
determine the normal boiling point (C)of PCl3
You need to clean up the post. I know you want normal boiling point of PCl3.
Is that dHofF S? Is that -288.07 dHo formation PCl3? Is that 311.7 dSo formation PCl3.
dGo = dHo-TdSo
dGo at boiling point is zero.
0 = dHo - TdSo
Plug in dHo and dSo and solve for T if I've interpreted those numbers right. You may have tried to make a table and since the spacing never turns out right the data was/is unclear to me.
I'm not sure about this and I think the best thing to do is to ignore my response until you've cleaned up the problem so I'm sure of the data.
To determine the normal boiling point of PCl3, we need to use the information given in the table of thermodynamic data. The boiling point of a substance is the temperature at which its vapor pressure equals the atmospheric pressure.
However, the given table does not provide vapor pressure directly. Instead, it gives the enthalpy of formation (∆HofF) and the entropy (S) values for PCl3. We can use these values to calculate the standard Gibbs free energy change (∆G) for the process.
The relationship between ∆G, ∆H, T (temperature), and ∆S (change in entropy) is given by the equation:
∆G = ∆H - T∆S
At the boiling point, the standard Gibbs free energy change (∆G) is zero. Therefore, we can set ∆G to zero and rearrange the equation:
0 = ∆H - T∆S
Solving for temperature (T):
T = ∆H / ∆S
Let's plug in the values for PCl3:
∆H = -288.07 kJ/mol
∆S = 311.7 J/mol-K (Note: we need to convert the unit to kJ/mol-K by dividing by 1000)
Converting units:
∆H = -0.28807 kJ/mol
∆S = 0.3117 kJ/mol-K
Plugging in these values into the equation:
T = -0.28807 kJ/mol / 0.3117 kJ/mol-K
T ≈ -0.9241 K/mol
Please note that the temperature (-0.9241 K/mol) obtained from this calculation does not make physical sense. It is likely that there may have been an error in recording the thermodynamic data. We cannot determine the normal boiling point of PCl3 with the given data.
I apologize for not being able to provide a definitive answer, but I hope this explanation helps you understand the approach and the limitations of the given information.