Sunday, February 27, 2011

Chloroform, the Wonderful Molecule!

 Do you ever have trouble sleeping at night? 
Do you toss and turn trying to catch a wink of sleep, then just wake up tired and exhausted in the morning? 
Suffer no more! 
Just put a little Chloroform in your handkerchief before bed and you are guaranteed the best sleep you have ever had!*

*Chloroform should never be used to help someone sleep for it is extremely dangerous to the human body. Side effects include nausea, headaches, and possible liver and kidney damage. 
Do you sleep just fine and get the suggested 8 hours of sleep every night?
Well don't worry! Chloroform has many other uses including

 Medical Purposes
Are you a doctor tired of your current anesthesia?
Do you want to change things up a bit? 
Try using Chloroform on your next patient to help numb them from the pain of their surgery!**
**Chloroform has recently been found to be toxic to the human body and should never be used as a type of anesthesia

Chloroform can even be used by Vetrinarians!
Do you prefer to help poor, sick animals over humans?
Do those poor, sick animals often have disgusting maggots in their wounds?

Then look no further than the wonderful Chloroform to kill all those nasty maggots! 

Chloroform can also be used in: 
  • Creating fluorocarbon-22 (a refrigerant)   
  • Photography as an industrial solvent
  • Dry cleaning as an industrial solvent 
  • The extraction and purification of some antibiotics  
These are just some of the many uses of the wonderful molecule Chloroform!

You know you want some, so
Pick it up at your local store today!

Polarity of Chloroform

A molecule can either be polar or non-polar depending on whether the molecule has an even distribution of electrons or not.
polar molecule does not have an even distribution of electrons. The electrical charges are not evenly distributed, causing one end to be more charged than the other.
non-polar molecule has an even distribution of electrons. Since the electrical charges are evenly distributed, they cancel each other out.

Chloroform can be written as CHCl3.
Therefore the Lewis Structure of Chloroform is:

As you can see, there are four bonds in CHCl3 but two different bonds: C-H and C-Cl

Finding the electronegativity value of each atom in the bond can help determine the energy flow and whether a molecule is polar or non-polar.

(green = Cl, black = C, white = H)
According to the Electronegativity Table, the electronegativity values of the atoms in CHCl3 are:
C - 2.5
H - 2.2
Cl - 3.2
In the picture below, the arrows represent the energy flow of each bond, for it goes from lower value to higher value.
So the arrow goes from  H (2.2) to C (2.5)
and from C (2.5) to Cl (3.2)
If the arrows all point to the same central atom, or if the arrows cancel each other out, then the molecule is non-polar, if not, than the molecule is polar.
 The arrows do not cancel each other out, for Cl is more negatively charged than C and H. Therefore Chloroform is a polar molecule because it does not have an even distribution of molecules, and one end is more negatively charged (Cl) than another (H).

Chloroform's Forces of Attraction

There are three possible types of forces of attraction: 

London Dispersion Forces 
London Dispersion forces occur between all molecules for they are weak temporary forces that attract two molecules when two atoms adjacent to each other have electrons in positions that cause the atoms to form temporary dipoles. 

Dipole-Dipole Forces  
Dipole Dipole forces only occur between polar molecules, for they are forces that attract the positive end of one molecule to the negative end of another adjacent molecule. 

Hydrogen Bonding 
Hydrogen Bonding only occurs in some polar molecules, for they are a type of dipole-dipole forces. Hydrogen bonding is a force that attracts the hydrogen of one molecule to the Nitrogen, Oxygen, or Fluorine of an adjacent molecule.  

Chloroform (CHCl3) uses London Dispersion Forces and Dipole-Dipole Forces to attract with another identical molecule, as shown in the picture below. *Note that the London Dispersion forces could not be showed because they are constantly forming all around the molecule, changing places. 

Chloroform uses London Dispersion Forces because all molecules regardless of polarity use them. Chloroform additionally uses Dipole-Dipole Forces because it is polar, and only polar molecules exhibit Dipole-Dipole forces, for polar molecules have oppositely charged ends that attract each other, while a non-polar molecule does not. Chloroform does not use Hydrogen Bonding because it does not contain any Nitrogen, Oxygen, or Fluorine that the Hydrogen can bond to.