Functional Groups - Ahmad Kilani

Functional Groups

Definition: a Functional group is a part of the organic molecule which is neither a C atom or an H atom.  There are many types of individual atoms or polyatomic ions that make a functional group, each having it's own properties.

For example, the functional group in this molecule would be Oxygen (Aldehyde).

There are many different types of functional groups, such as Aldehydes, Ketones, Halides and Nitro compounds, Esters, Ethers, Amines.  Each has a different functional group, and with it, different naming.


**We're only going to be looking at the first 3 functional groups (Aldehydes, Ketones, Halides And Nitro Compounds)

Halides and Nitro Compounds:

For the Halides, there are 4 elements that form this functional group;
-Fluorine (Fluoro)
-Bromine (Bromo)
-Chlorine (Chloro)
-Iodine (Iodo)

Nitro Compound (just one);
-NO2 (Nitro)

When naming a compound that contains a halide or nitro, use the name in the brackets.  For example;

  

To name this compound, we'd say 1-fluorohexane.  If there is more than one atom of the same element, use (di, tri, tetra etc.) prefixes.  Same naming rules apply for nitro.
**Don't forget that the names of the compounds are in alphabetical order (ie 1-bromo-2-fluorohexane)

Properties;
- Generally insoluble in water
- Compounds containing Fluorine are inert
- Compounds containing Bromine and Chlorine are more reactive, but still only react under extreme conditions
- Compounds with Iodine are very reactive
- Nitro compounds tend to be unreactive, yet explosive
- Nitro compounds generally have a nice smell

Aldehydes and Ketones:

Both Aldehydes and Ketones are organic molecules with double oxygen bond.  The difference between the two is that aldehydes have the double bond on either end of the compound.  Ketones on the other hands, can form double oxygen bonds with any carbon atom EXCEPT the ones at the ends.

Naming: For aldehydes, change the "e" in the alkane, alkene, alkyne, with "al"... So instead of propane, you would write propanal.  You never put a number before the compound's name if it's an alkane.  But you could write 2-propEnal (the 2 represents where the double bond is not where the O is)
- For Ketones, it's very similar, instead of changing the "e" at the end with "al", you change it to "one". So for example 3-propanone.  The number in front of the compound represents where the oxygen double bond takes place.

Properties;
- Aldehydes and ketones are easily oxidised
-  They're both liquids, the boiling point rises as the molecule gets bigger

Alcohols:

Alcohols are molecules with the functional group "OH".  Alcohols are basically an alkane with single or multiple OH functional groups.

One of the oldest types of man made alcohol is Ethanol

Naming: Like previous functional groups, you switch the "e" part of the molecule with "ol" this time.  With alcohol, more than one OH bond can take place, changing the name of the compound.  So you put a prefix for "ol" at the end of the name.  For example 1, 2, 4 - propanetriol.

Properties:
- Soluble in water
- The bigger the molecule the less soluble

Here's a quiz to test what you've learned today

Nick Kim-Alkene and Alkyne

This time we are going to find unsatrured hydrocarbon, means they are not single bond.

Alkene= double bonded
Alkyne=triple bonded

Naming is simialr to the alkane, you just need to put -ene instead of -ane. Same as alkyne -ene instead of -ane.

Ex,2-hexene

first you write down the number of carbon which is 6

c c c c c c

the 2 represent where double bond is

c-c=c-c-c-c

then put hydrogen

CH3-CH=CH-CH2-CH2-CH3

Notice where second carbon and third carbon only have one hydrogen.

Alkyne= Triple bond

This is very similar to the double bond

ex, 3-Hexyne

 Same as alkene, the number represent where the bond is, and it's triple, thus there is no hydrogen in third and fourth( between fourth and fifth sould be - sorry)

Here is the video that will help

Nick Kim- Organic Chemistry

Hydro Carbon- Molecule that only consist with hydrogen(H) and Carbon(C).
Since, Carbon has 4 valence electrons, it can bond to four sides.

Ex, Methane. Like you see Carbon goes middle because it is futher away from the full shell than hydrogen and Hydorgen bonds on four side.



This is called Alkane, it is satured hydrocarbon(single bond)

There are three ways to show Alkane 

what you see in example is full structure.

other one is called condensed structure. It looks like this.

ex, methane

CH3CH2CH3

and last one is called molecular formula

ex,methane

C3H8

 Number of carbon determine the name of alkane and also number of hydrogen.

Name you just need to memorize, but number of hydrogen is easy. You just need to multiple number of carbon and add 2. Ex) Methane CH4, 1x2=2 2+2=4 4 hydrogen

Note: not always hydrogen bonds to carbon, it can bon with other carbon

Alkyl group is an alkane which has one missing hydrogen,and it attaches to alkane group(branched hrdro carbon)

Ex,  CH3-Methyl=CH3 attached to propane.

When you named it is, 2-methly-Propane. the number only indicate which carbon it attached to, you can read from left to right or right to left.

Here are example





Chemical Bonding by Greg Sra

Bonding involves valence electrons only.
Atoms gain, lose, or share electrons until they have a stable octet.
There are 3 types of Bonding.
1) Ionic Bonds. An Ionic bond is formed when 2 electrons are transferred amongst each other.
2) Nonpolar Covalent bonds. A Nonpolar Covalent bond is formed when electrons are shared equally.
3) Polar Covalent Bonds. A Polar Covalent bond is formed when electrons are shared unequally.

Electrostatic Force
An electrostatic force exists between charged particles because of attraction or repulsion. Operates equally with each direction getting equal amounts of energy. Charged particles are put into crystal latices.
Basic Electrostatic Relationships:
1) Opposite charges attract each other.
2) Similar charges reject each other.
3) The longer the distance apart from 2 charged particles, the smaller the attracting force is between them.
4) The stronger the force of attraction is dependent on the charge of the particle.

Ionic Bonds
Metals usually lose valence electrons to non-metals, while non-metals gain the non-metals. This is an example of electrons being transferred. Once metals lose electrons they become positively charged ions or Cations. Once non-metals gain electrons they become negatively-charged ions or Anions. They are very strong with high melting points, its take massive amounts of energy to break them apart.

Electronegativity
The value of the tendency of an atom to take away  electrons from near by atoms.  Metals tend to have low electronegativity values in comparison Non-metals have higher values.  The scale that is applied to measure electronegativity is the Pauling Scale. This scales goes from Os & Fr which is 0.7 on the scale to 4.0 which is Fluorine.  Atoms with high values of Electronegativity will actively attract their own electrons and electrons from near by atoms. Ionization Energy also part takes in this.


Calculating Electronegativity Difference
The simple formula is below. In caps.
ENEGRY DIFFERENCE= {ENERGY 1 - ENERGY 2}


Non Polar Covalent Bonding
Covalent bonds like Ionic bonds are strong and need large amounts of energy to break them apart.Non polar covalent bonding has equal amounts  of energy spread apart. It is constructed when two atoms  don't have completed shells. They share one or more electron trying to satisfy the Octet rule. The electrons at the same time are attracted to the nucleus of each atom. Non-metals will not let go of their own electrons. Single molecules that contain intramolecular covalent bonds are attached together with intermolecular forces.

Polar Covalent Bonding 
Molecules that have electronegativity differences between .5-1.8 are thought to be covalent. But without equal sharing of electrons. This is called a Polar Covalent bond. An atom with a greater electronegativity will pull the electron toward its self and the electron will be closer to the atom with a higher electronegativity.

Super Chill Music

Kimistry got the slow beat goin.  Gonna make you warm and fuzzy while you read.

Electron Dot & Lewis Diagrams by Greg Sra

Electrons are represented by dots in electron dot diagrams. The nucleus is represented by the atomic symbol. There are 4 orbitals having at most 2 electrons per orbital. Each orbital is given an electron before it pairs up. The dots are put into 4 groups.With 8 electrons signifying a closed shell or noble gas.

Lewis Diagrams:

1) Firstly you must find out how many valence electrons are in your chosen elements. Adjust this number by subtracting an electron for each positive charge. Or by adding an electron for a each negative charge in the atom. Then count the electrons remaining.
** You want your atom to become stable, the only way to do this is by having 8 electrons in the outer shell.  (Hydrogen only needs 2 electrons)

2) Then select your central atom. A central atom is the atom that is the farthest away from a closed shell. (Metal Ion goes in center if available) H&F are an exception.Place the electrons so they fill each orbital.

3) Use the remaining valence electrons to fill out the orbitals. Place remaining electrons on the central atom.

4) Make multiple bonds if the central atom is not an octet.

 Covalent Compounds
Two atoms share a pair of electrons to create a full outer shell. This pair is called the Bonding Pair.

Lone pairs or non-bonding pairs are the pair of electrons which do not join together. Single bonds can be represented by 2 dots or a single line.

HISTROY OF THE PERIODIC TABLE

IN THE BEGINNINGGGG

-people believed everything was made up of fire, earth, wind, and water.

However, a russian chemist Dimitri Mendeleev would be the first person to write a periodic table.  He grouped different elements based on their properties.






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