Phosphorous trichloride is a polar molecule because the electronegativity of the chlorine atoms is greater than that of the phosphorous atom.
This uneven distribution of electron density results in a dipole moment, making the molecule polar.
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What is Phosphorous Trichloride?
Phosphorous trichloride is a colorless, poisonous gas with a pungent smell.
It is used in the production of plastics, pesticides, and other chemicals.
It is also used to make other chemicals, such as phosphates and chemical warfare agents.
Phosphorous trichloride does not occur naturally in the environment.
It was once a popular insecticide but is not currently registered for use in the United States.
Phosphorous trichloride is a highly toxic substance that can cause burning of the eyes, nose, throat, and skin.
It has been linked to an increased incidence of cancer in people as well as kidney damage.
Inhaling phosphorous trichloride is extremely hazardous as it will react with water in your lungs to form hydrochloric acid, which can lead to internal chemical burns and death from respiratory failure.
Only trained professionals using approved safety gear should handle this chemical.
What Does It Mean When a Substance Is Polar or Non-Polar?
When a substance is polar, it means that the atoms or molecules of that substance are asymmetrical.
This asymmetry creates a separation of charge, which gives the substance a polar nature.
This means that the substance will interact differently with other polar substances than with non-polar substances.
Polar substances are often able to dissolve in other polar substances because of the attraction between the positive and negative charges.
However, non-polar substances will not dissolve in polar substances because there is no attraction between the charges.
Non-polar substances are often more soluble in non-polar solvents.
Polar substances generally have higher melting and boiling points than non-polar substances.
This is because there are more interactions between the molecules in a polar substance, which require more energy to break when the substance melts or boils.
For example, water (H2O) is a polar molecule that will dissolve ionic compounds such as table salt (NaCl) because it has charges that attract the ions of Na+ and Cl-.
On the other hand, oil (a non-polar molecule) does not dissolve in water because it doesn’t interact with the charges in water.
Why is Phosphorous Trichloride Polar?
Phosphorous trichloride is polar because the chlorine atoms are on opposite sides of the phosphorous atom.
This causes a large difference in electronegativity between the phosphorus and chlorine atoms, which leads to a polar molecule.
Phosphorus trichloride has a dipole moment of 3 D, which means it is polar.
This big difference in electronegativity results in one side of the molecule having a slightly positive partial charge, and the other side having a slightly negative partial charge.
The partially positively charged end is called the “c+” end, while the partially negatively charged end is called the “-c-” end of the molecule.
Because the two halves are not symmetric, there is a dipole between them.
Chlorine atoms have three different pairs of electrons that are each affected differently by this charge difference.
The lone pair of chlorine spends more time closer to the “c+” end than the sp3 hybridized orbitals do, which results in a partial negative charge for chlorine at the “-c-” end.
This unequal sharing causes dipolarity in chlorides, bromides, and iodides.
Phosphorous trichloride molecules are polar because each atom contributes unevenly to the molecule’s electron density, making it unequally charged along its three axes.
There is greater electron density around one side of the phosphorus atom due to an increase in electronegativity on that side of the molecule.
This results in a partial negative charge at the other side of the molecule, while leaving one half with a positive partial charge.
Polar molecules are normally either linear bent, meaning that they have one or more atoms sticking out at an angle, or they are planar, meaning that they lie flat.
The phosphorus trichloride molecule is bent because the dipole of the molecule does not allow for it to lie flat.
Phosphorus trichloride has three electron pairs around phosphorus which can cause it to form coordinated covalent bonds with other molecules.
Phosphorus trichloride’s polarity makes this possible by allowing hydrogen bonding interactions between the substance and water.
In closing, phosphorous trichloride is polar because it has a high electron density on the phosphorus atom and a low electron density on the chlorine atoms.
This makes it good for making things like fertilizers, dyes, solvents, and other chemicals.
Phosphorous trichloride is very hazardous to the environment because of its high electron density on the phosphorus atom and low electron density on the chlorine atoms.
That means that it’s highly corrosive and reactive with other chemicals, such as water.
When exposed to water, it releases hydrochloric acid and phosphine gas.
That’s why you need to wear protective gear when dealing with this chemical, including a face mask, goggles, and work gloves.
It’s also very flammable and may explode if it gets too hot.
If Exposed To Phosphorous trichloride
If someone is exposed to phosphorous trichloride, they may notice the following symptoms:
- Eye pain and redness
- Fingertip swelling and blistering
- Cough, shortness of breath, chest pain, fever
If you think someone has been exposed to phosphorous trichloride, go immediately to the nearest emergency room.
It is important to remove soiled clothing quickly because liquid can continue to react with the skin even after it’s washed off.
It is possible for anyone to be exposed if they are near a spill or leak.
If you do work around this chemical, wear appropriate personal protective equipment (PPE) including approved respiratory protection, gloves, eye protection, and coveralls.
Before entering an area containing this chemical, you must have proper training on how to handle spills or leaks of chemicals.
Phosphorous trichloride can irritate or burn the skin, eyes, and mucous membranes. Immediately flush skin with soap and water for at least 15 minutes if phosphorous trichloride is on your skin.
If it’s in your eyes, hold them open and flush with lots of running water for at least 15 minutes. Get medical attention right away.
If swallowed, immediately get medical attention as soon as possible. Keep the victim calm and seek immediate medical help.
Emergency responders should wear some sort of self-contained breathing apparatus during spill response because there may be a risk of oxygen depletion from phosgene formation.
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