Module 4: Core Organic AS Flashcards
How do Monkeys help in naming alkanes?
Monkeys Eat Peanut Butter Politely Hurray is a Mnemonic which gives the initial letters for the first six alkanes: Methane; Ethane; Propane; Butane; Pentane; Hexane.
The structural formula of ethanol is …
…CH3CH2OH
What is the suffix of an aldehyde?
-al
What happens in Initiation?
e.g in the reaction of an alkene with Bromine
- UV radiation provides the energy to break the covalent bond in a bromine molecule
- The bond breaks by homolytic fission
- Radicals are formed
e.g- Br2 → 2Br•
What happens in Propagation?
eg. In the reaction of Bromine with Methane
- The products of the reaction are made. Note that one reactant is a radical and one product is a radical.
e.g- Br• + CH4 → CH3• + HBr
CH3• + Br2 → CH3Br + Br•
What happens in Termination?
eg. In the reaction of Bromine and Methane
- Any two radicals can combine
e. g- CH3• + Br• → CH3Br
Br• + Br• → Br2
CH3• + CH3• → CH3CH3
Which halogenoalkane produces a white precipitate when hydrolysed in the presence of silver nitrate?
Chloroalkane
What is the suffix of a carboxylic acid?
-oic acid
What is the difference between an Alkane and an Alkene?
Alkanes are saturated, they only have single bonds. Alkenes are unsaturated and contain C=C double bonds.
The molecular formula of ethanol is …
… C2H6O
what is a saturated hydrocarbon?
A hyrdrocarbon which contains single bonds only
Which reaction turns an alkane into an alkene?
Cracking
Define empirical formula
The smallest whole-number ratio of elements in a compound
eg: Molecular formula C5H10 has empirical formula CH2
What is the prefix for an Iodine containing compound?
iodo-
Which reaction turns an alkene into an alkane?
Hydrogenation
Which reaction turns an alkane into a haloalkane?
Radical substitution
The displayed formula for ethanol is …
what is an unsaturated hydrocarbon?
A hydrocarbon which contains 1 or more carbon-carbon double bonds
Which reaction turns an alcohol into a ketone?
Oxidation
What does it mean if a Hydrocarbon is classed as Aliphatic?
The carbon atoms are joined in an Unbranched (straight) or Branched Chain.
What does it mean if a Hydrocarbon is classed as Alicyclic?
Carbons are joined in Ring (Cyclic) structures.
What does it mean if a Hydrocarbon is classed as Aromatic?
Some or all of the carbon atoms are found in a Benzene Ring.
What is a Suffix and what is it used for?
- Added after the stem/name…
E.g. -ol
- Used to indicate different functional groups…
E.g. Alcohols
What is a Prefix and what is it used for?
- Added before the stem/name…
E.g. Iodo-
- Used to indicate the presence of side chains or functional groups…
E.g. Iodine Halogen (I)
What is the Suffix for an Ester?
-oate
What is the Suffix used when writing the name of specific Acyl Chlorides?
-oyl chloride
What is the functional group of a Ketone?
-C(CO)C-
What is the functional group of an Ester?
-COOC-
What is the functional group of an Aldehyde?
-CHO
What is the functional group of a Haloalkane?
-Cl -Br -I
What is the functional group of an Amine?
-NH2
What if the functional group of a Nitrile?
-CN
What is an Isomer?
Compounds which have the same molecular formula but different structural formulae.
We can have:
- Positional isomers (eg, branching)
- Functional group isomers (eg alcohol {CH3-CH2-OH} or ether {CH3-O-CH3})
- cis/trans E/Z isomers (involving C=C double bonds)
- Optical isomers (with chiral centres)
What effect does branching have on the boiling point of Alkanes/Isomers?
Decreases the Boiling point.
- Branching leads to poorer packing, so molecules further apart, reducing intermolecular forces
- Longer chains allow more electrons in same chain so more ways for the electrons to arrange themselves unevenly (so bigger instantaneous dipole)
what is meant by the term ‘reaction mechanisms’?
models that show the movement of electron pairs during a reaction.
what is homolytic fission?
homolytic fission occurs when a covalent bond breaks and each electron goes to a different bonded atom. This generates two highly reactive neutral species called Radicals.
What is a haloalkane’s reagents and observations?
- Silver nitrate, ethanol and water
- White precipitate- indicates chloro-
- Cream precipitate- indicates bromo-
- Yellow precipitate- indicates iodo-