Chapter 10 Organic Chemistry Flashcards
Organic chemistry
carbon containing compounds
Hydrocarbons
simplest group which only contains H-atoms and C-atoms
Alkane
c-c SINGLE bond
-ane
Alkene (simple explaination)
c-c DOUBLE bond
-ene
double bond is a functional group
Alkyne (simple explaination)
c-c TRIPLE bond
-yne
Methane
CH4
Two carbons
eth-
Three carbons
prop-
Four carbons
but-
Five carbons
pent-
Six carbons
hex-
Homologous series
two neighbouring molecules separate by a CH2 group
molecules have chemical similar properties (all burn), but slightly different physical properties (changes as chain lengthens)
Naming alkanes
- find longest chain
- numerate carbon atoms
- name substituents
= Number-name of subtituent - root name
Catenation
process in which many identical atoms are joined together by covalent bonds
= straught.chain, brached or cyclic structures
Functional groups
reactive part of molecules and commonly contain elements such as oxygen and nitrogen.
Atom or groups of atoms or bonds within a molecule that gives ots specific chracteristic reactions
Fractional distillation
physical separation process that uses differences in boiling points to separate the mixture into fractions of similar boiling points
Full structural formula
two-dimentional representation showing atoms + bonds + position
Condensed structural formula
atoms + bonds
Skeletal formula
line + vertex
represents carbon atoms present
(Structural) Isomer
compounds with same chemical formula but different structural formula + uniquw physical and chemical properties
Straight-chained pentane vs. branched pentane
S-c has a higher boiling point due to the strong forces between the chains
Brached structure results in weaker Van Der Waal forces, hence a lower boiling point
Classifying hydrocarbons
TWO ways
- Alkane, alkene and alkyne
- Open chained and aromatic compounds (rings with alternating c-c and c=c)
Saturated compound
carbon single-bonds
Unsaturated compound
carbon double and triple bonds
Alcohols
organic substances that contain an -OH (hydroxyl) group
Alcohol classification
- Primary - carbon connected to OH group is only connected to ONE other carbon atom
- Secondary - carbon connected to the OH group is connected to TWO other carbon atoms
- Tertiary - carbon connected to OH group is connected to THREE other carbon atoms
Halogenoalkanes
primary, secondary, tertiary classification
alkanes undergo free-radical substitution reactions with halogens, which is called homolytic cleavage/fission. Heterolytic cleavage/fission can also appear, where ions are formed as one atom takes all the shared electrons (creating + and -)
Oxidation of alcohols
Acidified potassium dichromate (VI) or potassium mangante (VII) are used.
K2Cr2O7 is oxidizing agent. CR2O7^2- (orange) is reduced to Cr^3+ (green).
The oxidation depends on alcohol type.
Oxidation of primary alcohols
Two stage process 1. Aldehyde -al C(H) = O through distillation 2. Carboxylic acid -ois acid C(OH) = O through reflux
Naming: functional groups are always number 1.
Oxidation of secondary alcohols
Ketone -one
-c-=O
Oxidation of tertary alcohols
Trick question. Tertiary alcoh cannot be oxidized. However, they burn, like all alcohols to form CO2 and H2O
Amines
Carbon bonded to Nitrogen
Classification depends on number of alkyl groups bonded to the nitrogen atom of the funtional group.
Naming: root loses -e, gaines -amine.
N signifies that substituent is bonded to the nitrogen atom.
Aromatic hydrocarbons
characterized by persence of benzene ring as all carbon atoms have equal electron density the molecule is symmetrical.
Hydrogenation
addition of hydrogen to unsaturated hydrocarbons in the presence of a catalyst
removing c=c double bonds increases the melting point, making a substance a solid rather than a liquid
e.g. saturated oils have prolonged shelf lives
The benzene molecule
C6H6
the bonds are intermediates between sinel bonds and double bonds
does not react as easily as alkenes as the delocalized electrons provide extra stability.
Reactions of hydrocarbons
Alkanes do not react readily as the c-c bonds are relatively strong.
Complete combustion
Incomplete combustion
Complete combustion
for all hydrocarbons, product is always CO2 and H2O
Incomplete combustion
product is mixture of Carbon, CO and H2O (and CO2) due to limited access to O2
Free-radicals
atoms/elements with an unpaired electron which makes them higly reactive
Volatility
tendency to change from liquid to gas
decreases as the length of the carbon chain increases.
Chloronation of alkanes
Initiation (free-radicals are formed by light)
Propagation
Termination (reactions are ended/come to an end)
Reactions of alkenes
Undergo addtion reactions double bond "splits" into two single bonds With bromine (brown); double bond = color disappears single or triple bond = color remains
Reactions
- Substitution
replacement of individual atoms with other small groups of atoms - Addition
two molecules added together to produce one molecule (alkenes) - Elimination
removal of two substituents from molecule
Reactions of alkanes
free-radical substitution
elimination to form unsaturated alkenes and alkynes
Polymerization
A process in which monomers react together to form a polymer.
Polymerization of alkanes
addition polymerization
- reaction of small monomers with c=c double bonds linked together to form a polymer
- a repeating structure is constructed/formed, which reflects the structure of the original monomer with double bonds replaced by single bonds and electrons released fromning new bonds to adjacent monomers.
halogentaion of alkenes
addtion of element halogen (Cl2 or Br2 or I2 or F2) = dihalogenated alkane
