lunes

Friday June, 4th, 2010

Aldehydes

Before we started class we had to recognize what R stands for.

R= Radical (which is any carbon molecule)

We recognized that in order for a molecule to be an Aldehyde it must have a Carbonyl group.


Aldehyde Also recognized as -CHO

When naming aldehydes:

  1. Identify the longest continuous chain of carbons with the carbonyl carbon as part of the chain.

  2. Number the carbon chain so that the carbonyl carbon is always number one.

  3. Locate and identify alphebetically the branched groups by prefixing the carbon number it is attached to. If more than one of the same type of branched group is involved use the prefixes di for 2, tri for three, etc.

  4. After identifying the name, number and location of each branched group, use the alkane name that represents the number of carbons in the continuous chain.

  5. Change the "e" ending and replace it with -al

It is like naming an alkane but only with a different suffix.

Example #1



propanal


2 methyl-propanal


Functional Group:The group of atoms responsible for the characteristic reactions of a compound. It is basically what makes that molecule special.
AlcoholHydroxylROHHydroxylhydroxy--olmethanol
Methanol
KetoneCarbonylRCOR'Ketoneketo-, oxo--oneButanone
Methyl ethyl ketone
(Butanone)
AldehydeAldehydeRCHOAldehydealdo--alacetaldehyde
Acetaldehyde
(Ethanal)

Original Names, the most used name in the lab.

Acetaldehyde- Ethanal
Formaldehyde- Methanal
etc.

Ketone


There are two forms of naming a ketone: formally and commonly. They are as follows:


Naming ketones formally:


  1. Identify the longest chain.

2. Name it as an alkane

3. Drop the suffix "e" and add "one"
4. Name it alphabetical order

5. The Carbon attached to the Oxygen should be relatively in the middle of the structure.
This website can help you :

http://www.cartage.org.lb/en/themes/sciences/chemistry/organicchemistry/Families/Somefamilies/Ketones/Ketones.htm




In naming ketones commonly,
  1. Identify the parent chain, it must include the carbonyl group

  2. Number the parent chain starting from the end closest to the carbonyl location.

  3. Identify the various branching groups attached to this continuous chain of carbons by name.

  4. Change the "e" ending and replace it with -one.
Ketones structural formula (Carbonyl group), notice there is no Hydrogen.

Example #2

this is called 3,Methyl- 2, Butanone

this is called diethyl ketone.


this is called :1)
2-pentanone or 2)
methyl 1-propyl ketone
Stefano Pinzon

Wednesday, June 2nd, 2010

Today in class we went deeper into the Alcohols, or actually into the effects of oxidation of alcohols.
The
OXIDATION OF A PRIMARY ALCOHOL creates an aldehyde.

This turns to:
H
|
CH3-C-OH
|
H

H
|
CH3-C=OH

That is because when oxidation occurs it is as if an Oxygen comes and takes away 2 Hydrogen (it only has two bonds) but since that leaves the C and the O with an extra bond each they then use then to connect with each other and that creates a double bond between them.

So basically an
ALDEHYDE has to have the -CHO group, and they come from a primary alcohol oxidating.

Then we saw what happens when a SECONDARY ALCOHOL oxidates.

You have a secondary alcohol:
OH
|
CH3-C-CH3
|
H
Which turns into the following when an oxygen "passes" by:
O
||
CH3-C-CH3
That is called a Ketone.

We were going to look at what the following grouping was (but we didn't have enough time due to our inability to stay quiet enough to listen and other interrupting events):
R
|
C=O
|
R

We had to look it up ourselves and put it here.
Which based on what I saw on different places is just another way of saying a CH group. so instead of writing the many CH3, you would write the R1 R2 or R3 which are the CH groups that are attached to the Carbon who is attached to the OH. (At least that is what I understood)

Victoria Bracamontes

Monday May 31st, 2010

In today's class we began learning the Molecules involving Carbon +Hydrogen+ Oxygen. In others words, Alcohols.

You must understand that all alcohols have a hydroxyl group. A hydroxyl group is an Oxygen attached by a covalent bond to a single Hydrogen.

Alcohols use the same formats as alkanes. To name alcohols,
  1. Determine the parent chain. The parent chain must be the longest that includes the carbon holding the OH group.

  2. Number according to the end closest to the -OH group regardless of where alkyl substituents are.

  3. The format is as follows: (location of branch)-(branch name)-(location of OH group)-(parent chain)

  4. Change the parent chain -e ending and replace it with an -ol.

Examples:
In this case it is called Methanol, due to is single Methyl and single OH.
As it says in the picture it is ethanol.

CH3-CH2-CH2-OH    In this case it is called 1-Propanol.

      OH       |   CH3-CH-CH3               In this case it is called 2-Propanol.

This is a harder example to identify:
                       H                        |                  H H H-C-H H                  | |   |   |                H-C-C---C---C-H                  | |   |   |                  H O   H   H                    |                    H              Parent chain: butane        -OH group location: 2    Substituents locations: 3-methyl               Alkane name: 3-methylbutane              Alcohol name: 3-methyl-2-butanol

!!!!!!!!!!!!!Just to make clear as i had done it wrong as well at the beginning is to add ol after the alkane has been name. This next example should clarify any problems, and if you are still confused please ask me!!!!!!!!!!!!!!!!!!!!


Alchohols containing more than one hydroxyl group are also called polyalcohols. Polyalcohols are named similarly to alcohols, with the exception of the prefix di-, tri-, etc before the -ol ending.
Example:

            H H             | |       H-C-C-H               | |         OH OH                                                                                                       This is called 
1,2-ethanediol
                     H H H            |    |   |        H-C-C-C-H             |    |   |          OH OH OH                                                                                                      This is called 
1,2,3-propanetriol

Kinds of Alcohols
There are three types of Alcohols:
1) Primary: an alcohol which has the hydroxyl radical connected to a primary carbon.
2) Secondary: an alcohol with its hydroxyl radical connected to a primary carbon which is 
  also connected to another carbon.
3) Tertiary: An alcohol in which the hydroxyl group is attached to a carbon that is joined to three carbons.
  
        
Ethers
Ethers was the easiest part of the class. There will always be an Oxygen in the middle, so to speak. You identify
the components and add ether without adding coordinates (no numbers).
For example:
      CH3-O-CH2-CH3
                        In this case it is called ethyl-methyl-ether. simple.

        CH3-CH2-O-CH2-CH3
   In this case it is called diethyl ether.

Extra Information: when you add a hydroxyl group to Benzene it is called a phenol
Stefano Pinzon

Friday May 28th, 2010

Yesterday was an interesting class (because of the fact that there was no physical classroom). We saw once more the Hydrocarbons subject, and yesterday (to be more specific) we saw ALKYNES. (every time i hear this word i remember the music video from the 1 semester jajaja).

Well, Alkynes are almost the same as Alkanes and Alkenes, but the differ in one thing: Alkynes have triple bonds. Also, the termination of the Alkynes is different, since their suffix is -dyne or -yne (depending on the prefix); for example: Ethyne

To name an alkyne there's this "importance" of the types of bonds that has to be considered:

  1. Double Bond (like the King of the Hill)
  2. Triple Bond (i don't know why it has less importance, but that's the way it is)
  3. Single Bond

Also, the "Hierchy" in Alkanes, Alkenes and Alkynes it's this (to know exactly from where we have to start counting the carbons):

  1. Longest Chain
  2. Closes Double Bond
  3. Closes Triple Bond
  4. Closest Branch
  5. Shortest Branch

If a chemical formula is the same in all this 5 characteristics, then they are "Simetrical", and you can start counting from wherever you want, since it would be the same on both sides.

Also, before the class ended, we saw a little about CYCLOALKANES: The only thing that has to worry you in naming this formulas are the quantity of branches that it has, how long it is and how many carbons has the longest "circle", like Methyl Cyclopentane (also, in this Alkanes we have to add the prefix Cyclo- because it's a Cycloalkane).

Homar Hurtado

Monday may 17th, 2010

In today's class we extended our knowledge in the area of organic chemistry.

-A Hydrocarbon is an organic molecule made up entirely of Hydrogen (H) and Carbon (C).
-It is also the simplest form of organic molecules.

There are two forms in which these molecules can take:
*Linear; appearance of molecule structure is "----------------" and may have branches as the image.
polymer with a chemical ...



*Cyclic; is a molecule which has no beginning or end. appearance as so:
File:Cyclic-phosphinoborane ...





We continued class by looking at the subcategories of linear molecules. Which are:


-Alkanes (single bonds)
-Alkenes (double bonds)
-Alkynes (Triple bonds)


Are class continued by looking specifically at the subcategory of Alkanes. We were going to begin to combine the prefix's we had learned with hydrocarbons. We would later be able to identify and create organic molecules that where hydrocarbons, had a linear shape, and were Alkanes.


Propane Structural FormulaIn this molecule, we may identify 3 Carbons, and 8 Hydrogens, in a linear shaped molecule.
Its name consists in: (hydrocarbon)
3 Carbons (C) = prop as the prefix
8 Hydrogens (H) +
And as it only has single bonds it is an Alkane, meaning it ends with ane.
----------------------------------------------------------------------------------------------
Propane (common household gas)



Example #2


Description Hexane displayed ...
In this molecule, we may identify 6 Carbons (C), and 14 Hydrogens (H), in a linear shape molecule. Its name consists in: (hydrocarbon)

6 Carbons (C)= hex as the prefix
14 Hydrogens (H) +
And as it only has single bonds it is an Alkane, meaning it ends with ane.
---------------------------------------------------------------------------------------------------------------------------------------
Hexane




We continued the class by learning how to identify branches and what to call the molecule with specific branches and those that pertained to linear shaped molecules.


 ... for example 3-methylpentane
The process in which to discover the name of such molecule:
1) Identify the longest chain , which in this case is the 5 Carbons shaded in blue. You may identify it as pentane from this point as well.
2)then you may identify the branches but numbering 1-5 starting from the side nearest to the branch. In this case it doesn't matter what side it is as the branch is located at "3" from either side.
3)Now naming the branch comes next, you use the same prefixes for the amount of carbons in the branch. In this case it is "Meth"and as its a part of the branch it is called Methyl, only adding yl.
4)Now you may put the information you discovered as follows:


Organic Molecule: 3-Methyl Pentane


Note: you must always order the branches alphabetically!!!!!!!!!!!!!!!!


Example #3


1 2 3 4 5 6 7 8 9 10
CH3-CH2-CH2-CH-CH-CH2-CH2-CH2-CH2-CH3
l l
CH3 CH3
1) The longest chain is 10 Carbons long, meaning it is a decane.
2)The branches are nearest to the left side of the chain. So we will number the chain for locating the branches. So the branches are located at 4 and 5.
3)Both branches are Methyl (due to one carbon in each branch).


Organic Molecule: 4,5-dimethyl-decane




Example #4


In this example it will remind you that the main chain has to be horizontal.




CH3 l
CH2
1 2 3l 2 1
CH3-CH2-C-CH2-CH3
l
CH3


1)The longest chain s 4 Carbons long, this is how it looks in a simpler form:
CH3
l
CH2
l
CH3-CH2-C-Ch2-CH3
l
CH3


It is a pentane.


2)The branches are equal distance from either side. It is located at "3"
3)In one branch it is methyl, and in the other it is bimethyl, adding them together gives you trimethyl.


the organic molecule: 3,3-trimethyl-pentane

Stefano Pinzon

Friday May 14th, 2010

First journal of the 3rd partial (time passes so quickly). Today we saw the intro of the 3rd partial main theme: ORGANIC CHEMISTRY

First of all, what's Organic Chemistry? simply, it's the the scientific study of the structure, properties, composition, reactions, and preparation of carbon-based compounds.

Now, knowing that we're going to hear carbon so many times that technically we are going to dream with it, we'll see an interesting characteristic of this necessary element for life.

Depending on the length of the carbon molecule and it's shape, the molecule is part of something different
(if it has linear shape it forms one thing, if it has an "L" shape it forms another thing, etc.)

The parts of an organic molecule are:
  • Prefix.- The first part of the molecule's name
  • Suffix.- The second part of the molecule's name

The prefix indicates the number of carbons that are in the molecule:
  1. Meth (Methane)
  2. Eth (Ethanol)
  3. Prop (Propane)
  4. But (Butane)
  5. Pent
  6. Hex
  7. Hept

There are different types of formulas that we're going to see and use in the rest of the semester, and they are:

  • CH4 -----> Molecular Formula (it tells us what do we have)
  • H-C-C-C-C-H -------> Structural Formula
  • CH3-CH3 -------> Condensed Formula


The phenomenon of using the same components but making different structures (and consequently different physical objects) is calledIsomery. A more "official" definition of it is this:

Isomery: "A molecule with the same molecular formula, but different structural formula".
Homar Hurtado

martes

Monday May 3rd

Today we learned about something new, it is called OSMOSIS. First of all, what is osmosis? (I didn't get it on the first time neither).

Osmosis is the movement of water through a semipermeable membrane; in high school words, "Osmosis is the action in which a cell let water pass through its wall (membrane)", we used the Girls and Boys example, but because of the dirty mind we have we understood very well and also laugh in the process.

Also, to understand better the teacher used the example of the fresh water fish and the salt water fish: If we put a cell of a salt water fish in a tank with fresh water a lot of water is going to enter to the cell and eventually is going to blow up (the cell, not the fish XD). The opposite thing occurs with a fresh water molecule and a salt water tank (the cell "dries up").

Another concept we saw was the Dyalisis: it is the movement of solute through a semipermeable membrane (the cell lets the particles of solute to go outside or inside so the concentration of both can be equal).

Homar Hurtado