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Flashcards in 4.1 Deck (61)
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1
Q

hydrocarbon

A

compound made of only hydrogen and carbon

2
Q

general formula

A

simplest algebraic formula e.g. C(n)H(2n+2)

3
Q

displayed formula

A

shows all bonds in compound

4
Q

skeletal formula

A

shows the carton changes as a line and doesn’t show the hydrogens e.g.. /\/\/\/

5
Q

structural formula

A

shows the structure split in to each carbon and the groups off it e.g. ch3ch2ch2ch3- butane if there is a group/atom off a carbon it is shown in brackets after the ch part

6
Q

alkenes

A

have a c=c double bond general formula CnH2n- unsaturated

7
Q

alkanes

A

only single bonds between carbons general formula CnH2n+2 - saturated

8
Q

Homologous series

A

a series of organic compounds that have the same functional group and each member differs from the next by CH2.

9
Q

characteristics of a homologous series

A

all share the same functional group, same functional groups, similar chemical properties, show a gradual change in physical properties as molar mass increases, can usually be prepared by similar methods

10
Q

prefixes by number of carbons

A

1-meth, 2-eth, 3-prop, 4-but, 5-pent, 6-hex, 7-hept, 8-oct, 9-non, 10-dec

11
Q

alkane suffix

A

-ane

12
Q

branch suffix

A

-yl

13
Q

cycloalkanes prefix+suffix

A

cycle-ane

14
Q

alchohol suffix

A

-ol

15
Q

aldehydes suffix

A

-al

16
Q

keytones suffix

A

-one

17
Q

carboxylic acids suffix

A

-oic acid

18
Q

esters suffix

A

alkyl -oate

19
Q

rules for naming compounds

A

1) count carbons in longest chain
2) number carbons so that carbon 1 is closest to the functional group
3) any side chain or functional group numbered and given prefix

20
Q

functional group of alkenes

A

c=c

21
Q

haloalkanes functional group

A

-x where x=F,Cl,Br,I

22
Q

aldehyde functional group

A

-CHO

23
Q

alkane functional group

A

c-c

24
Q

keytone functional group

A

C-CO-C

25
Q

carboxylic acid functional group

A

COOH

26
Q

alcohol functional group

A

-OH

27
Q

aromatic compounds

A

contain at least one benzene ring

28
Q

aliphatic compounds

A

dont contain a benzene ring - carbon atoms joined together as straight of branched chains

29
Q

alicyclic compounds

A

subgroup of aliphatic compounds where carbon atoms are joined in a ring structure

30
Q

structural isomer

A

they have the same molecular formula but different structural arrangements

31
Q

boiling point of alkanes

A

as chain length increases so does the boiling points but the boiling point increases by less each time

32
Q

branching and boiling point

A

branches reduces boiling point because there is less surface contact between chains => reduced dipole-dipole interactions

33
Q

heterolytic bond fission

A

breaking a covalent bond forming oppositely changed ions

34
Q

homolytic bond fission

A

breaking a covalent bond forming two radicals

35
Q

radical

A

species with an unpaired electron -very reactive

36
Q

sigma bond

A

a single covalent bond -> electron orbitals overlap between atoms

37
Q

pi bond

A

second bond in a double covalent bond - the electrons could be in two places it is weaker than the sigma bond

38
Q

free radical substitution

A

type of reaction involving a chain reaction in which a covalent bond is broken forming radicals that go one to make more radicals and taking the place of other atoms in the species

39
Q

problems with free radical substitution

A

cant control the reaction, free radicals are very reactive, if there is enough chlorine further substitution could eventually be replaced

40
Q

electrophile

A

an electron pain acceptor

41
Q

addition reaction

A

something is added to a species only one product formed

42
Q

hydrogenation

A

addition reaction, nickel catalyst, alkene product, C2H4 + H2 -> C2H6

43
Q

direct hydration

A

C2H4+H2O (gas) -> C2H5OH needs high pressure (6Mpa) and phosphoric acid catalyst

44
Q

curly arrow mechanism

A

curly arrow shows a pair of electrons that will either come from bonds or a species

45
Q

steps of free radical substitutions

A

intiation, propagatioon, termination

46
Q

markownikoffs rule

A

when two products are formed one is formed in a larger quantity. The major product is formed via the most stable carbocation. the carbon in the c=c bond attached to the most carbons is most stable

47
Q

stereoisomers

A

compounds with the same structural formula but with a different arrangement is space

48
Q

why are stereoisomers not found in alkanes

A

only found in alkenes because the c-c bond can rotate but c=c bonds cant

49
Q

when can you have stereoisomers

A

only when both carbons in ate c=c bond have 2 different atoms or groups attached to the carbon

50
Q

z isomers

A

higher priority groups/atoms are on the same side of the c=c bond i.e. both above or below

51
Q

e isomers

A

higher priority groups/atoms are on the opposite sides of the c=c bond i.e. one above or one below

52
Q

to determine priority of the groups in an isomer

A

higher mr = higher priority

53
Q

addition polymerisation

A

an alkene undergoes a addition reaction with itself, all atoms in the original alkene are used to from the polymer , long hydrocarbon chain formed

54
Q

Landfill disposal

A

Large holes are dug and lined to stop any contaminants seeping into water table.
•Rubbish is then added and compacted
•When full the site is covered over with soil and landscaped
•This creates anaerobic conditions with limited water
•Decomposition is slowed for biodegradable waste
•Many plastics are non-biodegradable so do not break down and can be a danger to wildlife

55
Q

Recycling

A
  • Plastics are sorted into different types
  • This is expensive as it requires lots of workers or high technology to automate the process
  • Plastics are cleaned, melted down and reshaped
  • Limited market as companies concerned about quality and contamination
  • About 7% recycled currently
56
Q

Combustion for energy

A

Plastics are mainly organic and can be burned to produce electricity
•They contain a large number of carbons which releases carbon dioxide during combustion
•This is a greenhouse gas and is linked to global warming and climate change
•Depending on the plastic other toxic chemicals like HCl (from PVC) can be made
•These gases can be removed by using gas scrubbers
•This contains a base Calcium oxide that neutralises the acidic gas

57
Q

Organic feedstock disposal method

A

After waste plastics have been sorted into different types then a series of chemical reactions can be used to break the plastic polymers up into smaller more useful chemicals
•These more useful chemicals can be used for other industrial reactions

58
Q

Biodegradable polymers

A

To have a biodegradable plastic it must be able to be broken down by environmental conditions or microorganism
•Sometime a biodegradable polymer like plant starch is mixed with an addition polymer
•This means over time the polymer can be broken down making the polymer chain smaller and the material biodegradable
•However there is concerns over the small pieces of addition polymers may still cause hazards to the ecosystem

59
Q

Photodegradable plastics

A

Photodegradable plastics break down chemically using energy with wavelengths similar to light
•Addition polymers can have bonds (ester bonds) within the structure that are weakened by absorption of light
•Addition polymers can have additives that are affected by light which then weakens the polymer.
•Once exposed to light the polymer starts to breakdown in an irreversible process.
•However photodegradable plastics in landfill may not be exposed to sufficient light to degrade

60
Q

Bioplastics

A

If only biodegradable plastic is used then it is a bioplastic
•Plant starch can be used to make bin bags
•If the starch is derived from sustainable farming methods then the material could be classified as ‘carbon neutral

61
Q

Compostable plastics

A

To be fully compostable a plastic must decompose landfill material as quickly as compost would form from grass clippings and other green waste
•The only products should be carbon dioxide, water, inorganic compounds and biomass
•Polylactic acid is an example of this and is used in disposable utensils and drinking cups