organic chemistry keywords

Question 1

compounds made up of carbon and hydrogen only

Answer 1

hydrocarbons

Question 2

the formula that tells us the simplest ratio of the different atoms present in a molecule

Answer 2

empirical formula

Question 3

the formula that tells us the actual numbers of each type of atom in a molecule

Answer 3

molecular formula

Question 4

the formula that tells us about the atoms bonded to each carbon atom in an organic molecule, e.g. CH3CH=CH2

Answer 4

structural formula

Question 5

a drawing of a molecule that shows all the atoms and bonds within the molecule

Answer 5

displayed formula

Question 6

a simplified version of the displayed formula, having all the symbols for C and H atoms removed as well as the C to H bonds, but still showing the C to C bonds left in place

Answer 6

skeletal formula

Question 7

an atom or group of atoms in an organic molecule that determine the characteristic reactions of a homologous series

Answer 7

functional group

Question 8

a formula that represents a homologous series of compounds using letters and numbers. e.g. the (it) for the alkanes is CnH2n+2. By substituting a number for n in the general formula you get the molecular formula of a particular compound in that homologous series

Answer 8

general formula

Question 9

a shared pair of electrons bonding two atoms together

Answer 9

single covalent bond

Question 10

single covalent bonds, formed by the ‘end-on’ overlap of atomic orbitals

Answer 10

sigma (σ) bonds

Question 11

multiple covalent bonds involving sideways overlap of p atomic orbitals

Answer 11

pi (π) bonds

Question 12

compounds with the same molecular formula but different structural formulae

Answer 12

structural isomers

Question 13

when the position of the functional group varies in each isomer

Answer 13

position isomerism

Question 14

when there are different functional groups present in each isomer

Answer 14

functional group isomerism

Question 15

when the structure of carbon ‘skeleton’ differs in each isomer

Answer 15

chain isomerism

Question 16

compounds with the same structural formula with atoms arranged differently in space

Answer 16

stereoisomers

Question 17

geometric isomerism in unsaturated compounds or cyclic compounds depending usually on the presence in the molecule of a pair of substituted groups (as unsymmetrically substituted methylene groups) so that the stereoisomers have comparable substituents on either the same or opposite sides of the molecule. different phy and chem properties

Answer 17

cis-trans isomerism

Question 18

Stereoisomers who are non-superimposable mirror images. The isomers display identical characteristics in terms of molecular weight as well as chemical and physical properties. However, they differ in their effect on the rotation of polarized light.

Answer 18

optical isomerism

Question 19

a carbon atom with four different groups attached, creating the possibility of optical isomers. but actually optical isomers chiral centrenya bs atom apa aja, gk mesti C.

Answer 19

chiral centre

Question 20

a type of bond breaking where both the atoms of each end of the bond leave with one electron from the pair that formed the covalent bond, producing free radicals

Answer 20

homolytic fission

Question 21

species produced when a bond breaks homolytically. very reactive atom or molecule that has a single unpaired electron

Answer 21

free radical

Question 22

the first step in the mechanism of free-radical substitution of alkanes by halogens. It involves the breaking of the halogen-halogen bond by UV light from the Sun

Answer 22

initiation step

Question 23

reaction involving the formation of free radicals, requiring an input of energy to break a covalent bond, resulting in two free radicals

Answer 23

initiation step

Question 24

a step in a free-radical mechanism in which the radicals formed can then attack reactant molecules generating more free-radicals, and so on, chain reaction.

Answer 24

propagation step

Question 25

the final step in a free-radical mechanism in which two free radicals react together to form a molecule, with no free radicals generated

Answer 25

termination step

Question 26

an alkyl group carrying a single positive charge on one of its carbon atoms, e.g. +CH2CH3

Answer 26

carbocation

Question 27

alkyl groups tend to 'push' the electrons away from themselves. we say that the electron-donating nature of alkyl groups has a ... on adjacent groups

Answer 27

positive inductive effect

Question 28

an acceptor of a pair of electrons

Answer 28

electrophile

Question 29

a donator of a pair of electrons

Answer 29

nucleophile

Question 30

an organic reaction in which two reactant molecules combine to form a single product molecule

Answer 30

addition reaction

Question 31

a reaction in which a small molecule is removed from an organic molecule

Answer 31

elimination

Question 32

a reaction that involves the replacement of one atom, or group of atoms, by another

Answer 32

substitution

Question 33

the breakdown of a compound by water, which is often speeded up by reacting with acid or alkali

Answer 33

hydrolysis

Question 34

the addition of O2, removal of e- or increase in oxidation number of a substance; in organic chemistry refers to a reaction in which O atoms are added to a molecule and/or H atoms are removed from a molecule

Answer 34

oxidation

Question 35

the removal of O2, addition of e- or decrease in oxidation number of a substance; in organic chemistry it is the removal of O atoms from a molecule and/or addition of H atoms to a molecule

Answer 35

reduction

Question 36

saturated hydrocarbons with the general formula CnH2n+2

Answer 36

alkanes

Question 37

compounds of hydrogen and carbon only in which the C-C bonds are all single covalent bonds, resulting in the maximum number of hydrogen atoms in their molecules

Answer 37

saturated hydrocarbons

Question 38

the reaction in which halogen atoms substitute for hydrogen atoms in alkanes. the mechanism involves steps in which reactive free radicals are produced (initiation), regenerated (propagation) and consumed (termination)

Answer 38

free-radical substitution

Question 39

unsaturated hydrocarbons with a carbon-carbon double bond. their general formula is CnH2n

Answer 39

alkenes

Question 40

compounds of hydrogen and carbon only whose molecules contain carbon-to-carbon double bonds (or triple bonds)

Answer 40

unsaturated hydrocarbons

Question 41

the process in which large, less useful hydrocarbon molecules are broken down into smaller, more useful molecules

Answer 41

cracking

Question 42

a long-chain molecule made up of many repeating units

Answer 42

polymer

Question 43

a small, reactive molecule that reacts to make long-chain molecules called polymers

Answer 43

monomer

Question 44

the reaction in which monomers containing carbon-to-carbon double bonds react together to form long-chain molecules called polymers

Answer 44

addition polymerisation

Question 45

the mechanism of the reaction in which a nucleophile attacks the carbon atom in a carbonyl group and adds across the C=O bond, e.g. aldehydes or ketones reacting with HCN

Answer 45

nucleophilic addition

Question 46

the steps in a nucleophilic substitution in which the rate of the reaction (which is determined by the slow step in the mechanism) involves only the organic reactant, e.g. in the hydrolysis of a tertiary halogenoalkane

Answer 46

SN1 mechanism

Question 47

the steps in a nucleophilic substitution in which the rate of the reaction (which is determined by the slow step in the mechanism) involves two reacting species, e.g. in the hydrolysis of a primary halogenoalkane

Answer 47

SN2 mechanism

Question 48

an alcohol in which the C atom bonded to the --OH group is attached to one other C atom (or alkyl group)

Answer 48

primary alcohol

Question 49

an alcohol in which the C atom bonded to the --OH group is attached to two other C atoms (or alkyl groups)

Answer 49

secondary alcohol

Question 50

an alcohol in which the C atom bonded to the --OH group is attached to three other C atoms (or alkyl groups)

Answer 50

tertiary alcohol

Question 51

renewable fuels, sourced from plant or animal materials, such as ethanol from sugar (extracted from sugar canes) fermented with yeast.

Answer 51

biofuels

Question 52

the reaction between an alcool and a carboxylic acid (or acyl chloride) to produce an ester and water

Answer 52

esterification

Question 53

a reaction in which a water molecule is removed from a molecule, e.g. in the ... of an alcohol to give an alkene

Answer 53

dehydration

Question 54

an organic compound containing both an -OH and a -CN group, e.g. 2-hydroxypropanenitrile, CH3CH(OH)CN

Answer 54

hydroxynitrile

Question 55

a reaction in which two organic molecules join together and in the process eliminate a small molecule, such as water or hydrogen chloride

Answer 55

condensation reaction

Question 56

an aqueous solution of AgNO3 in excess NH3 solution, sometimes called ammoniacal silver nitrate solution. it is used to distinguish between aldehydes and ketones. it gives a positive 'silver mirror' test when warmed with aldehydes, but no change is observed with ketones

Answer 56

Tollens' reagent

Question 57

an alkaline solution containing copper(II) ions used to distinguish between aldehydes and ketones. A positive test is one in which the clear blue solution gives a red/orange ppt when warmed with aldehydes, but no change is observed with ketones

Answer 57

Fehling's solution

Question 58

a technique for identifying compounds based on the change in vibrations of particular atoms when infra-red radiation of specific frequencies is absorbed

Answer 58

infra-red spectroscopy

Question 59

aldehydes and ketones addition with HCN, substitution in halogenoalkanes

Answer 59

nucleophilic

Question 60

addition to alkenes

Answer 60

electrophilic