module 4 Flashcards
define the term hydrocarbon
A hydrocarbon is a compound containing carbon and hydrogen only
define the term fuctional group
A functional group is the part of the organic the molecule that is largely responsible for the molecule’s chemical properties
define the term homologous series
A homologous series is a family of compounds with
the same functional group and similar chemical
properties
whose successive members differ by the addition of
a –CH2– group
define the term homolytic fission
In homolytic fission, a covalent bond is breaks with
each bonded atoms takes one of the shared pair of
electrons from the bond.
e.g. H3C–CH3 → H3C• + •CH3
define the term heterolytic fission
In heterolytic fission, a covalent bond is breaks with
one of the bonded atoms taking both of the
electrons from the bond.
e.g. H3C–Cl → H3C+ + Cl–
define the term structural isomers
Structural isomers are compounds with the same
molecular formula but different structural formulae and arrangements in space
define the term empirical formula
The empirical formula is the simplest whole-number
ratio of the atoms of each element present in a
compound
define the term structural formula
The general formula is the simplest algebraic
formula for any member of a homologous series
define the term displayed formula
A displayed formula shows the relative positioning
of all of the atoms in a molecule and the bonds
between them
define the term skeletal formula
The skeletal formula is the simplified organic
formula, shown by removing hydrogen atoms from
alkyl chains, leaving just a carbon skeleton and
associated functional groups
define the term electrophile
An electrophile is an electron pair acceptor, e.g. Br2
define the term nucleophile
A nucleophile is an electron pair donor, e.g. OH–
define the term radical
A radical is an atom or groups of atoms with an
unpaired electron, e.g. Cl•
define the term saturated
A compound with a carbon to carbon multiple bond
double or triple bond
effect on chain length on boiling point
increased chain length =
- greater London forces
- larger surface area of contact
effect on branching on boiling point
more branching =
- weaket London forces
- smaller surface area of contact
Complete combustion of alkanes formula
CxHy + (x + y/4) O2 —> xCO2 + y/2 H2O
What overap does a pi bond have
Sidewards overlap
Conditions for E/Z isomerism
- a C=C double bond
- different groups attached to each carbon atom of the double carbon to carbon bond
Difference between cis-trans and E/Z
cis-trans needs one of the attached groups to be the same
Test for unsaturation
(Bromine water test)
Add bromine water (orange colour) to the solution
If the solution turns from orange to colour then the solution was unsaturated meaning there was a C=C double bond present.
If there was no colour change then there was no unsaturated compund present.
define the term dehydration
a reaction in which a water molecule is removed from the starting material
define the term nucleophiles and give examples
species that donate a lone pair of electrons
OH-
H2O
NH3
1-chlorobutane observation
a white precipitate forms very slowly
1-bromobutane observation
a cream precipitate forms slower than 1-iodobutane but faster than 1-chlorobutane
1-iodobutane observation
a yellow precipitate forms rapidly
use of anhydrous calcium chloride
drying hydrocarbons
use of anhydrous calcium sulfate
general drying
use of anhydrous magnesium sulfate
general drying
define the term fragmentation
in the mass spectrometer, some molecular ions breaking down into smaller pieces knows as fragments.
define the term elemental analysis
use of percentage composition data to deternmine the empirical formula
define the term mass spectrometry
use of the molecular ion peak from a mass spectrum to determine the molecular mass; use of fragment ions to identify sections of a molecule
define the term infrared spectroscopy
use of absorptions peaks from an infrared spectrum to identify bonds and functional groups present in the molecule
define the term aliphatic
carbon atoms are joined to each other in unbranced or branched chains, or non-aromatic rings
define the term alicyclic
carbon atoms are joined to eachother in ring structures (cyclic). some with or without branches
define the term aromatic
some or all of the carbon atoms are found within a benzene ring
