Topic 10: organic chemistry

• the chemistry of carbon is much more extensive than that of any other element with many compounds of carbon. the macromolecules that build up life are made of carbon

  • 4 valence electrons, abundance and high bonding capacity

O2 is stronger than O3 and O2 absorbs more UV

resonance makes C_C bonds too strong to break easily

the fact that carbon atoms can join together to form chains and rings

components in a chemical mixture are separated using their different boiling points.

a family of hydrocarbons

Alkanes are the least reactive, alkene is more reactive, and alkyne is the most reactive

4

larger hydrocarbons have more LDF making it more polarizable = Higher Melting/boiling points (more bonds need to be broken to boil)

Different compounds that have the same molecular formula

Atom/group of atoms that give the molecule its chemical properties. They are the reactive part of the compound

A series of compounds that have the same functional group - Each member differs by a unit of CH2

melting/boiling point increases as it now has more bonds to break through

Structures of straight/ branched chains/ rings of carbon atoms

1. Alkanes

2. Alkenes

3. Alkynes

4. Cyclic

Carbons bonded by single bonds (sigma bonds) making them fully saturated hydrocarbons. very stable. CnHn+2

A molecule that has at least one double bond (pi bond) between two carbon atoms, resulting in an unsaturated hydrocarbon (not the maximum number of hydrogens are bonded to the carbon atom). Unstable/reactive. CnH2n

A molecule that contains at least one triple bond between carbon atoms, wrestling in an unsaturated hydrocarbon. CnH2n-2

Structures based on that of benzene. Essentially the functional groups are the benzenes

• A ring of 6 carbon atoms that are bonded to one another with double and single bonds with a resonance structure C6H6

• -the electron in the double bond are shared equally among all the carbons

• Very stable molecule because of its resonance

• “Pi electrons are delocalized in its arrangement “

When the alkyl groups are found on the same side of the carbon then it’s cis and if it’s on opposite sides than it’s trans

just named as “halogen prefix”benzene

benzene with a carboxyl (COOH) substituent group

Benzene with a hydroxyl (OH) substituent group

Benzene with an ammonia substituent group

Benzene with a methyl (CH2) substituent group

Sometimes in hydrocarbon chains benzene is treated as a substituent and it is simply named using “phenyl”

Functional group: hydroxyl
Naming: anol
Example: Ethanol
General Formula: CnH2n+1OH

More polar than hydrocarbons - as hydrocarbon chain gets longer it becomes more non-polar Form hydrogens bonds because of the hydroxyl group Higher melting/boiling points since it has hydrogen bonds

an OH group (hydroxide)

Primary Alcohol 1 o : bonded to 1 carbon alkyl Secondary Alcohol 2o: bonded to 2 carbon alkyl Tertiary Alcohol 3 o : bonded to 3 carbon alkyl

Includes more than one hydroxyl group

Functional group: aldehydes (carbonyl)
Suffix: anal
Example: Ethanal
General formula: RCHO

Lower melting/ boiling points than alcohols since they don’t have the OH group for hydrogen bonding Also are less soluble in water than alcohols However, C=O bond is polar so they are more soluble and have higher boiling and melting points than hydrocarbon

Functional Group: Carbonyl
Suffix: anone
Example: Propanone
General formula: RC(O)R'

Lower melting/boiling points and less soluble in water than alcohols However, C=O bond is polar so they are more soluble and have higher boiling and melting points than hydrocarbon

R-O-R If it’s not the priority it’s represented with “oxy” always as a prefix

A polar C-O bond, however can’t form hydrogen bonds More soluble and higher melting/boiling points than hydrocarbons  Less polar and lower melting/boiling points than alcohols

R-C(=O)(-O)-R’ - Made with a carboxylic like group in the middle however the hydrogen atom is replaced with another carbon chain Main chain suffix end is “oate”

Since it has no hydrogen bonding it is less polar than alcohols and carboxylic acids but it is still more polar than ethers and hydrocarbons  More soluble and have higher mp/bp point than ethers and hydrocarbons but less soluble and lower mp/bp than alcohols and carboxylic acids (as an aqueous solution)

R-C-N-R’ - A carbon group bonded to a nitrogen (the nitrogen group can be bonded to up to two hydrocarbon chains or 2 hydrogens) - Functional group is NH2 Main chain suffix end is “amine”

SMALL amines are soluble in water as N-C bonds are polar Higher mp/bp than hydrocarbons but because it’s less polar than O-C groups it is lower than alcohols

Primary Amine 1 o : 1 hydrocarbon chain  Secondary Amine 2 o : 2 hydrocarbon chains Tertiary Amine 3 o : 3 hydrocarbon chains

R-C(=O)(-N)-R’ - Similar to an ester but has an N instead of a single bonded O - Functional group is CONH2 Main chain suffix end is “amide”

Smaller amides are water soluble as C=O is polar and forms hydrogen bonds with N Higher mp/bp than ketones/aldehydes but a lower polarity than carboxylic acids When maximum number of hydrogens are bonded to the amide it has a higher boiling point because it now has more hydrogen bond

Initiation Propagation Termination

The making of a free radical (1 reaction) Splits the electron equally, both atoms get one of the previously shared electrons - Forming the free radicals with the divided atoms

Splits the electron unevenly, one atom gets all the previously shared electrons

Splits the electron equally, both atoms get one of the previously shared electrons Written as X•

The radical swapping around until the compound and the radical form another compound (2 reactions) Radical takes hydrogen from the hydrocarbon forming a free radical hydrocarbon Then the free radical hydrocarbon reacts with an element (that was originally the free radical from the initial step) and forms a compound with it and there is now an extra free radical of the original free radical

Shows all the radicals combining to form their respective compounds (3 reactions)

the radicals original compound + the hydrocarbon → (catalyst of UV) hydrocarbon with the element radical + the hydrogen and the element radical

NHumber of chemical bonds between a pair of atoms - represents it’s stability Number of covalent bonds divided by the number of atoms involved in the compound

Bond order and bond length are inversely proportional to each other: as bond order increases bond length decreases bond length which tells us how strong it is: Smaller bond lengths means it is a stronger bond and vice-versa

O 2 divides into two oxygen free radicals Bond order of 2 → longer bond length → Weaker → less energy needed to break  Only needs UV-C

O 3 divides into 1 oxygen free radical and then an oxygen compound  Bond order of 1.5 -> Shorter bond length → stronger → more energy needed to break Needs UV-B

Stable compounds that break down when it absorbs UV radiation → forms free radicals destroys the ozone molecules when it is broken down by the UV light

These reactions can stop when the free radicals of NOx and CFCs collide together and form their own compound

Molecules with many repeating identical parts Made up of monomers  Unreactive

DNA, Proteins, oils, fats etc

Building blocks of polymers Extremely reactive

Cheaper to produce, and are chemical and biological UNREACTIVE Have many properties

Involving an alkene monomer - Producing a long alkane chain  Double bonds break and then a bond that is adjacent to the monomers form on BOTH sides of the original monomer

Polyethylene (made from a chain of ethylene) ← Ethene Polypropylene (made from a chain of propylene) ← Propene Polyvinylchloride  Polystyrene (made from a chain styrene) ← Phenylethene  Teflon

Involves the condensation of one or two monomers with functional groups  Producing amides and esters and water

, a condensation reaction is a type of chemical reaction in which two molecules are combined to form a single molecule, usually with the loss of a small molecule such as water. If water is lost, the reaction is also known as a dehydration synthesis

Functional group: hydroxyl Naming: anol Example: Ethanol General Formula: CnH2n+1OH

Functional group: ether Suffix: oxy alkane Example: Methoxy Propane General formula: ROR'

Functional group: Carboxylic acid Suffix: anoic acid. Example: Ethanoic Acid General formula: RCOOH. OH groups make these even more polar than other functional groups, so very soluble in water very high melting/boiling points

Functional group: Ester Suffix: alkyl anoate Example: Methyl Propanoate General formula: RCOOR'

Functional group: Amine Suffix: anamine Example: Ethanamine General Formula: RNH2

Functional Group: Amine Suffix: anamide Example: Ethanamide General Formula: RC(O)NH2

orange→ colourless

no colour change