Organic chemistry Flashcards
structures of methane, ethane, ethene, ethanol, ethanoic acid
o 1 carbon has the prefix of: Meth-
o 2 carbons: Eth-
o 3 carbons: Prop-
o 4 carbons: But-
o Remember the first 4 prefixes using MEPB Monkeys Eat Peanut Butter
-suffix of any compound refers to the functional group
o Alkanes –ane (C-C) e.g. ethane
o Alkenes –ene (C=C) e.g. ethene
o Alcohols –ol (OH) e.g. ethanol
o Carboxylic acids –anoic acid (-COOH) e.g. ethanoic acid
type of compound present, given a chemical name ending in -ane, -ene, -ol, or -oic acid or a molecular structure
● -Ane : alkane o Functional group (same group of atoms in each molecule that makes an alkane) is C-H / C-C (NOT C=C) ● -Ene : alkene o Functional group is C=C ● -Ol : alcohol o Functional group is OH ● -Oic acid : carboxylic acid o Functional group is COOH
Name and draw the structural formulae of the esters which can be made from unbranched alcohols and carboxylic acids, each containing up to four carbon atoms
o Alcohol + carboxylic acid -> ester + water
o Methanol + Ethanoic acid -> Methyl Ethanoate + H2O
● How to name esters
o (prefix of alcohol + yl) + (name of carboxylic acid minus the “oic acid” + oate)
o E.g. Meth-yl Ethan-oate
● the alcohol part is to the right normally with an H from
the –OH functional group being lost.
● The carboxylic acid part is to the left with an OH from
the –COOH functional group being lost
● H + OH → H2O (a by-product.
fuels
coal, natural gas and petroleum
methane as the main constituent of natural gas
- methane as the main constituent of natural gas
- methane= CH4
petroleum
Petroleum is a mixture of hydrocarbons
properties of molecules within a fraction
●The shorter the molecules, the lower the temperature at which that fraction evaporates or condenses – and the lower its boiling point.
● Shorter the molecules, the less viscous it is. (more runny)
uses of the fractions
– refinery gas for bottled gas for heating and
cooking
– gasoline fraction for fuel (petrol) in cars
– naphtha fraction for making chemicals
– kerosene/paraffin fraction for jet fuel
– diesel oil/gas oil for fuel in diesel engines
– fuel oil fraction for fuel for ships and home heating systems
– lubricating fraction for lubricants, waxes and polishes
– bitumen for making roads
Homologous series
a ‘family’ of similar compounds with similar chemical properties due to the presence of the same functional group
general characteristics of a homologous series
- Same general formula
- Similar chemical properties
- Common methods of preparation
Describe and identify structural isomerism
- Isomers are compounds that have same molecular formula but different structural formula.
- Properties quite simmilar
- M.p and B.p differ
properties of Alkanes (exemplified by methane)
● Generally unreactive, except in terms of burning
bonding in alkanes
- Contain single bond
- General formula: Cn H2n +2
substitution reactions of alkanes with chlorine
● Halogen + alkane –(UV)-> halogenoalkane + hydrogen halide oe.g.Br2+C2H6-(UV)->C2H5Br+HBr
● Must be in the presence of ultraviolet radiation (UV)
manufacture of alkenes and of hydrogen by cracking
● Hydrocarbons can be cracked to produce smaller, more useful molecules. This process involved heating the hydrocarbons to vaporise them.
● The vapours are:
o Either passed over a hot catalyst (silica or alumina)
o Mixed with steam and heated to a very high temperature (temperature
in the range of 600-700 ̊C) so that thermal decomposition reactions can occur.
● The products of cracking include shorter chain alkanes and alkenes (or hydrogen)