S3.2 Functional groups: Classification of organic compounds

what is organic chemistry

the field of chemistry where carbon based compounds are studied

what is catenation

the process by which many identical atoms are joined together by covalent bonds

can carbon undergo catenation

yes

what is the result of catenation of carbon

straight chain, branched or cyclical structures

what do organic compounds include

fuels, paints, dyes, alcohol, plastics, industrial solvents, drugs and medicines, foods, pesticides and fertilizers

what are the different ways you can represent an organic compound with a formula

empirical formula, molecular formula, structural formula, skeletal formula

what does an empirical formula represent

the simplest ratio of atoms present in a molecule

what does the molecular formula describe

the actual number of atoms present in the molecule

can the structure be deduced from an empirical formula or a molecular formula

no

what do structural formulas describe

the structure of a compound

what are the three types of structural formulas

full structural formula/displayed formula, condensed structural formula, skeletal formula

what is a full structural or displayed formula

two dimensional representations showing all the atoms and bonds, and their positions relative to relative to one another in a compound

what is a condensed structural formula

all the atoms and their relative positions are shown, but some or all of the bonds are ommitted

what is a skeletal formula

the most basic representation of the structural formula, where the carbon and hydrogen atoms are not shown but the end of each line and each vertex represents a carbon atom, the atoms present in the functional groups are also included

draw the skeletal formula of propane

draw the skeletal formula of propan-2-ol

draw the skeletal formula of propanone

what is a functional group

an atom or a group of atoms that gives organic compounds their physical and chemical characteristics

what is the functional group of alcohols

hydroxyl (OH)

what is the functional groups of aldehydes

carbonyl (O)

what is the functional group of ketones

carbonyl (O)

what is the difference between ketones and aldehydes

aldehydes have their functional groups at the end of the molecule whereas ketones have their functional groups in the middle of the molecule

what is the functional groups of carboxylic acids

carboxyl (COOH)

what is the functional group of ethers

alkoxy (R-O-R)

what is the functional group of the primary amines

amino (NH2)

what is the functional group of the amides

amido (NH2O)

what is the functional group of esters

ester (COO)

what is the functional group of aromatics

phenyl (benzene ring)

what does aliphatic mean

a molecule containing no aromatic rings

what is a homologous series

a family of compounds that can be grouped together based on similarities in their structure and reactivity

what is the name of the CH2 group

methylene

what is the general formula of the alkane species

CnH2n+2

what are the alkenes

a homologous series of unsaturated hydrocarbons that contain a carbon=carbon double bond

what is the general formula of the alkenes

CnH2n

what is the general formula of the alkyne series

CnH2n-2

draw but-2-yne

what is the general formula of the alcohols

CnH2n+1OH

what type of reactions can alcohols undergo

combustion reactions and oxidation reactions

what is the general formula of the aldehydes

CnH2nO

what is the general formula of carboxylic acids

CnH2nO2

what is the general formula of ethers

R-O-R' where R and R' are alkyl or aryl groups that can be identical or different

what is the general formula for members of the amine homologous series

CnH2n+3N

what are the three types of amines

primary, secondary, tertiary

in primary amines

the nitrogen atom is bonded to two carbon atoms

in secondary amines

the nitrogen is bonded to two carbon atoms

in tertiary amines

the nitrogen is bonded to three carbon atoms

what is the general formula of esters

R-COO-R'

what are esters derived from

carboxylic acid

what are the applications of esters

flavourings, medication, solvents, explosives

what is the general formula of amides

CnH2n+1NO

what is the functional group of amides

-CONH2

draw propanamine

draw dimethylamine

draw trimethylamine

what is the functional group of a compound responsible for

the types of characteristic reactions the compound undergoes

what happens to the physical properties of substances in a given homologous series

the physical properties such as the melting and boiling point change gradually with each successive member

why do the physical properties change down a homologous series

the length of the carbon chain increases each time, altering the intermolecular forces

what can you use to measure the boiling points for successive members of a homologous series

simple distillation apparatus and a temperature probe

what can the close correlation between carbon chain length and boiling point enable you to predict

the properties of neighbouring members of a homologous series

what does the trend in increasing boiling point result from in homologous series

stronger LDFs as the carbon chain increases in length

how is the fact different members of a homologous series will condense at different temperatures used by the petrochemical industry

crude oil is separated using fractional distillation

what is fractional distillation

a physical separation process where crude oil is vaporized and then passed through a column, as the vapour rises through the column, it cools and will condense at different levels in the column

what is a substituent in organic chemisty

any part of an organic compound that is not part of the longest carbon chain

what doe IUPAC nomenclature rules help

helps chemists to avoid confusion, eliminate language barriers, and freely communicate knowledge

give an overview of the IUPAC naming system

prefixes in alphabetical order, principal parent chain, suffixes indicating saturation or unsaturation of the principle chain, suffix indicating the principle group

what are structural isomers

compounds that have the same molecular formula but different structural formulas

what is the template for namine alkenes

substituent locant, substituent name, parent chain, double bond locant, ene

when naming halogenoalkanes, how is the position of the halogen substituent identified

by the locant on the parent chain

what is the substituent name of iodine

iodo

when are locants for the substituent groups omitted in halogenoalkanes

for derivatives of methane and ethane because all locants for the substituent are equivalent

what do all alcohols contain

at least one OH functional group

how is the carbon chain numbered in alcohols

such that the hydroxyl group has the lowest possible locant, taking priority over other substituents or carbon-carbon double bonds

which members of a homologous series does not require a locant for its functional group

the first two

which two compounds have the C=O functional groups

aldehydes and ketones

where is the carbonyl group found in aldehydes

always at the end of the carbon chain

what is the suffix for aldehydes

al

what type of compound has a carbonyl group that is not located at the terminal position in the primary carbon chain

ketone

how is the carbon chain numbered in ketones

such that the carbonyl group has the lowest possible locant

what is the suffix for ketones

one

how are carbon chains numbered in carboxylic acids

starting with the functional group

what are chain isomers

structural isomers with different lengths of carbon chains

what are positional isomers

structural isomers where the position of the functional group changes

does changing the position of the functional group on the parent carbon chain affect the chemical properties of compounds

yes

how can you classify compounds depending on the position of their functional groups

as primary, secondary or tertiary

a primary carbon atom is

bonded to one other carbon atom

a secondary carbon atom is bonded to

two other carbon atoms

a tertiary carbon atom

is bonded to three other carbon atoms

what does amine classification depend on

the number of alkyl groups bonded directly to the nitrogen atom of the functional group

what are functional group isomers

structural isomers with the atoms arranged differently such that they have different functional groups

what type of compounds can be functional group isomers of one another

hydroxyl + alkoxy, aldehydes + ketones, ester + carboxyl

what are stereoisomers

isomers with the same molecular formula, connectivities and bond multiplicity but have different spatial arrangements of the atoms

what are the two major classes of stereoisomers

conformational isomers and configurational isomers

describe how conformational isomers occurr

if a molecule contains two groups bonded together by a single bond, these groups can rotate about the single bond to form different conformational isomers

how can configurational isomers be interconverted

only by breaking and reforming bonds

what are the subcategories of configurational isomers

cis-trans isomers and optical isomers

are groups bonded to the unsaturated carbon atoms able to rotate about the carbon-carbon double bond

no

what is a chiral carbon

a carbon atom bonded to four different atoms or groups of atoms

what is a chiral carbon also known as

a stereocenter or asymmetric centre

what type of molecules exhibit optical isomerism

molecules with one or more chiral carbon atoms

what are a pair of optical isomers known as

enantiomers