Chapter 8 - Organic Chemistry Flashcards
what are hydrocarbons
molecules made of only hydrogen and carbon atoms
what are saturated hydrocarbons
contain single bonds
fully surrounded by atoms
what are unsaturated hydrocarbons
multiple bonds between carbons
not fully surrounded by atoms
what are cyclic compounds
molecules where carbon atoms are arranged in a ring
what is the alkane formula
2n +2
what are alkanes
qazwsx
single bonds between carbon atoms
go through combustion and substitution reactions
what is the alkene formula
2n
what are alkenes
qazwsx
a double bond between carbon atoms
start with ethene as first member
go through combustion and addition reactions
what is the alkyne formula
2n-2
what are alkynes
qazwsx
triple bond between carbon atoms
starts with ethyne as first member
combustion and addition reactions
what is the aromatic series
a family of unsaturated, cyclic hydrocarbons. simplest member is benzene
naming hydrocarbons
- determine the longest chain of carbon atoms. this chain must contain the double, triple bond if present
- number carbons starting from end closest to functional group, double bond, alkyl branch
- name each branch by the prefix, number of carbons, and the -yl suffix. indicate what number they are on. if there a 2 identical molecules we say di-. this applies for all branches
- indicate what number the multiple bond is on and place between name.
what are condensed formulas
also known as semi structural formulas show the structure of molecules with letters
when do you use brackets in a condensed formula
to show branches
when CH2 is continually repeated
what are functional groups
a group with a common bond, atoms or group of atoms that give a molecules specific properties
alcohols
function group = -OH = hydroxyl group ends with the suffix -ol
Carboxylic acids
function group = -COOH = carboxyl group ends with suffix -anoic acid
properties of alcohols
high points (h bonding)
solubility decreases with size (non polar region grows)
reactions are combustion, esterification/condensation
properties of carboxylic acids
high points (hydrogen bonding from -OH)
smaller molecules are soluble for same reason as alcohols
reactions are esterification/condensation
have a pungent odour
weak acidity
esters
functional group= -COO = ester group
follows the format of ____yl _____anoate
first is no. of carbons in alcohol
second is in carboxylic acid
What are fossil fuels
natural fuels derived from the fossil remains of living organisms, which have been altered by heat and pressure underground
where do hydrocarbons come from
crude oil/petroleum
how is crude oil formed
in ancient times, plant and animal life fell to the sea floor and became covered with sediment.
high pressure and temperature over millions of years converted the once living material into hydrocarbons.
explain fractional distillation
the process of using a fractionating tower to separate different types of alkanes found in crude oil. petroleum is boiled to create gases which have different condensation temperatures. this roughly separates the different molecules as they cool at different temps in the tower.
what is catalytic cracking
the cracking of alkanes is the process of breaking large useless hydrocarbons into smaller more useful ones. this can be done with high heat or catalysts.
describe a complete combustion reaction
where there is a plentiful supply of oxygen
hydrocarbon + oxygen – carbon dioxide + water
characterised by a blue flame
describe an incomplete combustion reaction
where oxygen is limited
hydrocarbon + oxygen – carbon or carbon monoxide + water
characterised by an orange flame
what is the limewater test
the limewater test is where the products of a combustion reaction are fed by pipe into a calcium hydroxide solution. if carbon dioxide is present it creates a precipitate of calcium carbonate, turning there whole solution cloudy
describe a substitution reaction
alkane + halogen – haloalkane + bi-product
in the presence of UV or high heat
describe an addition reaction
double bonds are broken to bond to a new molecule.
there is never a bi-product
catalyst not needed as double bonds are already repelling…
describe an esterification reaction
where an alcohol and carboxylic acid come together to form an ester with water as a bi-product. due to water loss, it is sometimes called a condensation reaction.
properties of an ester
relatively low boiling point (dipole-dipole only)
strong smell
