Unit 3 Topic 5 Flashcards
Organic chemistry: Organic synthesis
What is an Addition reaction?
An addition reaction is when two reactant molecules join to form one product
What is a Substitution reaction?
A substitution reaction is when one or more atoms are substituted between molecules
What is an Elimination reaction?
An elimination reaction is when one or more atoms are removed from a molecule, this leaves at least two products
What is a Condensation reaction?
A condensation reaction is when two molecules join together, with the loss of a small molecule (usually water)
What is a Hydrolysis reaction?
A hydrolysis reaction is when water is used to split a large molecule into two. The H attaches to one part, the OH attaches to the other. This leaves two new smaller molecules
What is an Oxidation reaction?
An oxidation reaction is when the oxygen to hydrogen ratio of an organic molecule increases
NOTE: More oxygen/less hydrogen per molecule
What is a Reduction reaction?
A reduction reaction is when the oxygen to hydrogen ratio of an organic molecule decreases
1. NOTE: Less oxygen/more hydrogen per molecule
What is a Neutralisation reaction?
A neutralisation reaction is when an organic acid is neutralised, producing salt and water.
If the base is a carbonate, carbon dioxide will also be produced
What is Bond fission?
Bond fission is when bonds in reactant molecules are broken
What is Bond formation?
Bond formation is when new bonds are formed in products
What is Homolytic bond fission?
Homolytic bond fission is when a sigma bond is broken evenly so each atom retains one electron from the bond. This happens in a non-polar bond and two neutral radicals are formed
What is a Free radical?
A free radical is an atom/molecule that contains an unpaired electron. It has no overall charge as its proton num = electron num
What is a Neutral radical?
A neutral radical is a highly reactive radical, it will react with any atom with an unpaired electron. It will also attack another molecule in order to pull an electron from it
What is a Propogation reaction?
A propogation reaction is a reaction which keeps a chain reaction going
What is a Termination reaction?
A termination reaction is a reaction that removes free radicals from the system without replacing them, this brings the chain reaction to an end
What is Heterolytic bond fission?
Heterolytic bond fissioon occurs when a polar covalent bond is broken unevenly, so both electrons from the sigma covalent bond are retained by the more electronegative atom. Resulting in two oppositely charged ions
What does a Single headed arrow show?
A single headed arrow shows the movement of a single electron
what does a Double headed arrow show?
A double headed arrow shows the movement of a pair of electrons
What is a Nucleophile?
A nucleophile is a chemical species that is either neutral with an area of high electron density or negatively charged. They are attracted to partially/fully positive atoms/ions and can donate a pair of electrons to form a dative bond.
What is an Electrophile?
An electrophile is either a positive ion, or a neutral molecule that is deficient in electrons. They are attracted to partially/fully negative atoms/ions and can accept an electron to forma dative bond
What is a Leaving group?
A leaving group is a fragment of a molecule that leaves with a pair of electrons in heterolytic bond fission
How can you test for the presence of an Alkene?
The addition of bromine water tests for the presence of an alkene, as a double carbon to carbon bond decolourises bromine water
How do you identify a Halide ion?
A halide ion can be identified by reacting with silver nitrate solution. A precipitate of the silver halide will form and a colour will be observed
NOTE: The colour depends on the precipitate formed
What is an Sn1 reaction?
An Sn1 reaction is a nucleophilic substitution reaction involving one species in the rate determining step and occuring in at least two steps
NOTE: 1 refers to num species, not num steps
What is Inductive Stabilisation?
Inductive stabilisation is when more alkyl groups increase the stability of a carbocation
What is an Sn2 reaction?
An Sn2 reaction is a nuceluphilic substitution reaction involving two species in the rate determining step and occuring in one step
NOTE: 2 refers to num species not num steps
What is Steric Hinderence?
Steric hinderence is when alkyl groups occupy a large space and block a nucleophile from attacking the +ve carbon
What is an Ether?
An ether is molecule made up of two alkyl groups joined together through an oxygen atom
R-O-R’
What is an Alkoxide?
An alkoxide is an ion that is formed by the loss of a hydrogen ion from the hydroxide group of an alcahol
What is a Nitrile?
A nitrile is an organic compound with a cyano group attached to the terminal (end) carbon
What is Markovnikov’s rule?
Markovinkov’s rule states that when a hydrgoen halide or water is added to an un-symmetrical alkene, the hydrogen atom will attached to the carbon with the most hydrogen atoms already attached to it
NOTE: This rule is used to predict major/minor products
Name a reducing agent:
Lithium aluminium hydride is a reducing agent, used to supply hydrogen
What is a Primary alcahol?
A primary alcahol has its OH group on the terminal (end) carbon atom. It can be oxidised to an aldehyde and further oxidised to a carboxylic acid.
What is a Secondary alcahol?
A secondary alcahol has its OH group on an internal carbon atom. It can be oxided to a ketone and can’t be oxidided any further
How can you test for an Aldehyde? (2)
You can test for an aldehyde using Tollen’s reagent or Fehling’s solution
NOTE: Tollen’s goes colourless to silver, Fehling’s goes blue to red
What is a Halogenation reaction?
A halogenation reaction is when one of the hydrogen atoms is substituted with a halogen atom
What is Alkylation?
Alkylation is when one of the hydrogen atoms is substituted with an alkyl group in the presence of an aluminium chloride catalyst
What is Nitration?
Nitration is when one of the hydrogen atoms is substitued with a nitro (NO2) group in the presence of concentrated sulfuric acid and concentration nitric acid
What is Sulfunation?
Sulfunation is when one of the hydrogen atoms is substitued with a sulfuric group
