Basic concepts of organic chemsitry

Question 1

define structural formulae

Answer 1

the minimal details that show the arrangement of atoms in a molecule

Question 2

define displayed formulae

Answer 2

shows the relative positioning of atoms and the bonds between them

Question 3

define skeletal formulae

Answer 3

simplified organic formulae, shown by removing hydrogen atoms from alkyl chains, leaving just the carbon skeleton and associated functional groups

Question 4

define homologous series

Answer 4

series of organic compounds that have the same functional group but with each successive member differing by -CH2

Question 5

define general formulae

Answer 5

simplest algebraic formulae of members of a homologous series

Question 6

define alkyl group

Answer 6

a group of atoms attached to other atoms or groups of atoms, with the general formula CnH2n+1

Question 7

what’s an aromatic compound

Answer 7

one that contains a benzene ring

Question 8

general formula for alkanes

Answer 8

CnH2n+2

Question 9

general formula for alkenes

Answer 9

CnH2n

Question 10

general formula for alcohols

Answer 10

Cn(H2n+2)O

Question 11

define functional group

Answer 11

a group of atoms responsible for the characteristic reactions of a compound, eg -NH3, -OH

Question 12

what’s an aliphatic compound

Answer 12

one that contains C and H joined together in straight chains, branched chains or non-aromatic rings

Question 13

what’s an alicyclic compound

Answer 13

aliphatic compound arranged in non-aromatic rings (with or without side chains)

Question 14

what are structural isomers

Answer 14

compounds with the same molecular formula but different structural formulae

Question 15

what’s positional isomerism

Answer 15

• where the same functional group is attached at different points on the chain (but same molecular formula)
• different physical properties, chemical properties may also be different too

Question 16

what’s functional group isomerism

Answer 16

• where one isomer has a different functional group to the other (but same molecular formula)
• very different physical and chemical properties

Question 17

what’s chain isomerism

Answer 17

• where one isomer has a different arrangement of the hydrocarbon chain
• similar chemical properties but different physical properties as boiling point eill differ

Question 18

what’s homolytic fission

Answer 18

when a bond breaks and each bonding atom receives one e- from the bonded pair, forming two radicals

Question 19

what’s heterolytic fission

Answer 19

when a bond breaks and one bonding atom receives both e- from the bonded pair, forming ions

Question 20

how do you show movement of e- pair

Answer 20

double headed arrow

Question 21

how do you show movement of single e-

Answer 21

single headed arrow

Question 22

define addition reactions

Answer 22

two reactants join together to make one product

Question 23

define substitution reactions

Answer 23

an atom or group of atoms is replaced by a different atom or groups of atoms

Question 24

define elimination reactions

Answer 24

the removal of a small molecule from a larger one, often water