Module 4 - Chapters 11-13 P2 Flashcards
what are organic compounds?
Any compounds containing carbon
saturated hydrocarbons
single carbon-carbon bonds only (more saturated with hydrogen)
unsaturated hydrocarbons
one or more carbon-carbon double or triple bonds (less saturated with hydrogen)
compound with a triple bond
alkyne
general formula of alkane
CnH2n+2
general formula of alkyl
CnH2n+1
general formula of alkene
CnH2n
general formula of alcohol
CnH2n+1 OH
general formula of carboxylic acids
CnH2n O2
general formula of ketones
CnH2nO
definition of homologous series
A series of organic compounds having the same functional group but with each successive member differing by CH2
Functional group
part of the molecule largely responsible for the molecule’s chemical properties
what functional group does an amine group have?
NH2
name three classifications of hydrocarbons
aliphatic, alicyclic and aroMATic (not aroMANtic)
aliphatic hydrocarbons
carbon atoms arranged in chains (branched or unbranched)
alicyclic hydrocarbons
carbon atoms joined in a ring (cyclic) structure (branched or unbranched)
aromatic hydrocarbons
some or all of the carbon atoms are found in a benzene ring (C6H6)
general formula of alkyne
CnH2n-2
general formula of cycloalkane
CnH2n
prefix for naming carbon chain with 12 carbon atoms
Dodec
prefix for naming carbon chain with 20 carbon atoms
Eicos
functional group of aldehyde
CHO (O double bonded to C), functional group is always on carbon 1 for aldehydes
suffix (ending) for aldehydes
-al
functional group for ketones
C(CO)C (chain of 3 carbons and O double bonded to middle one)
suffix (ending) for ketones
-one
functional group for carboxylic acids
COOH (one O double bonded to C and one bonded as part of OH to carbon)
suffix (ending) for carboxylic acids
-oic acid
functional group for esters
COOC (one O double bonded to C, other O single bonded to two Cs)
suffix (ending) for esters
-oate
functional group for acyl chloride
COCl (O double bonded to C)
suffix (ending) for acyl chlorides
-oyl chloride
suffix (ending) for amines
-amine
functional group for nitriles
CN (N triple bonded to C)
suffix (ending) for nitriles
nitrile
molecular formula
shows the number and type of atoms of each element present in a molecule, doesn’t show the bonding
definition for empirical formula
the simplest whole-number ratio of the atoms of each element present in a compound
displayed formula
shows the relative positioning of all of the atoms in a molecule and the bonds between them, each line represents a pair of shared electrons
structural formula
shows the arrangement of the atoms in a molecule by showing clearly which groups are bonded together
skeletal formula
a simplified organic formula with all of the carbon and hydrogen labels removed along with any bonds to hydrogen atoms, this just leaves a carbon skeleton and any functional groups
definition of structural isomers
molecules with the same molecular formula but different structural formula
what are the three types of structural isomers?
chain, positional, functional group
chain isomerism
when the carbon atoms are moved on the original carbon chain to form structural isomers
positional isomerism
when the basic carbon skeleton remains unchanged but important groups (such as functional groups) are moved around on that skeleton
functional group isomerism
when molecules containing different functional groups have the same molecular formula, functional groups can be changed (e.g. ketones/aldehydes)
what are the components of crude oil?
petroleum gases, petrol (gasoline), kerosene (paraffin), diesel, lubricating oil, heavy fuel oil, bitumen
use of petroleum gases
used in domestic fuel
use of petrol/ gasoline
cars
use of kerosene/ paraffin
aircraft
use of diesel
cars
properties of small molecules in crude oil
low bpt, light in colour, easy to ignite, not viscous
properties of large molecules in crude oil
high bpt, dark in colour, difficult to ignite, thick/viscous if liquid (bitumen = solid at room temp)
why does increase in chain length in hydrocarbons in crude oil increase bpt?
london forces increase because more electrons are present and increasing chain length increases surface contact
why does branching of alkanes decrease bpt?
- results in decreased points of surface contact between molecules so london forces decrease.
- branching also prevents molecules packing together as easily so molecules are further away and intermolecular forces decrease
what type of covalent bond bonds each carbon in an alkane?
sigma bonds ( σ) , formed by the overlapping of orbitals with each overlapping orbital containing one electron
why is it not possible for alkanes to have stereoisomers?
the sigma bond allows free rotation of atoms around the molecule
why do alkanes have a low reactivity?
- the sigma bonds are very strong (high bond enthalpy)
- C-C bonds are non-polar
- C-H bonds are considered non-polar due to the similar electronegativity of C and H
combustion
when alkanes react with oxygen to form carbon dioxide and water, heat is also produced
why are alkanes used as fuels?
- readily available
- easy to transport
- easy to burn in a plentiful supply of oxygen without releasing toxic products
composition of natural gas
typically 80% methane with varying proportions of ethane, propane and butane
alkane which is a component of petrol
heptane
incomplete combustion
in a limited supply of oxygen, hydrogen atoms always oxidised to water but carbon may form carbon monoxide or soot (soot = singular carbon atoms)
carbon monoxide
colourless, odourless, highly toxic
what are the two types of fission to break covalent bonds?
homolytic and heterolytic fission