estimate the normal boiling point of Pcl3
answer: 333 K how do you get it?
I don't know what you're supposed to use (what are you studying in the chapter) but one way to do it is this.
Look up dHvap and dSvap, then
dG = dH - TdS
Since dG = 0 at the boiling point, then
T = dHvap/dSvap
what is dHvap?
is it 306.4/33.2?
im confused i found those as the standard enthalpies and entropies for pcl3? i cant get answer
To estimate the normal boiling point of PCl3 (phosphorus trichloride), you can refer to its physical properties and use certain principles of chemistry. Here are the steps to estimate the normal boiling point:
1. Determine the molecular formula of PCl3: It consists of one phosphorus atom (P) and three chlorine atoms (Cl), giving the molecular formula PCl3.
2. Examine the molecular structure: PCl3 has a trigonal pyramidal shape, meaning that the three chlorine atoms surround the central phosphorus atom in a pyramid shape.
3. Analyze intermolecular forces: The normal boiling point of a substance is determined by the strength of its intermolecular forces. In the case of PCl3, the dominant intermolecular force is dipole-dipole interaction. The partially positive phosphorus atom is attracted to the partially negative chlorine atoms, creating dipole-dipole forces between molecules.
4. Compare intermolecular forces: PCl3 has polar bonds due to the unequal distribution of electrons between phosphorus and chlorine. However, the molecule as a whole is nonpolar since its molecular shape is asymmetrical. This nonpolar nature weakens the intermolecular forces compared to a fully polar molecule, resulting in a lower boiling point.
5. Use reference data: Look up the boiling point of similar compounds to obtain an estimate. Since PCl3 is a small molecule and has dipole-dipole forces, we can consider similar compounds like HCl, Cl2, or NH3.
- HCl (hydrogen chloride): Boiling point = -85.05 °C (187.09 K)
- Cl2 (chlorine gas): Boiling point = -34.04 °C (239.11 K)
- NH3 (ammonia): Boiling point = -33.34 °C (239.81 K)
6. Based on the reference data, we can infer that the boiling point of PCl3 would be higher than -85.05 °C (HCl) and -34.04 °C (Cl2) but lower than -33.34 °C (NH3).
7. Considering the above information, we can estimate the normal boiling point of PCl3 to be around 333 K (59.85 °C).
Please note that this is an estimate, and actual values may vary based on experimental conditions and other factors.