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A level Chemistry > Organic > Flashcards

Organic Flashcards

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1
Q

Define empirical formula

A

The simplest whole number ratio of atoms in a molecule

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2
Q

Define molecular formula

A

Gives the actual number of atoms of different elements in a molecule

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3
Q

Define displayed formula

A

Shows every atom and every bond in a molecule

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4
Q

Define structural formula

A

Shows arrangement of atoms in a molecule without showing every bond

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5
Q

Define skeletal formula

A

Drawn as lines with each vertex being a carbon atom. Carbon atoms not drawn, assumed each atom has all unspecified bonds as C-H

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6
Q

Give the suffixes for:
An alkane
An alkene
An alcohol
An aldehyde
A ketone
A carboxylic acid

A

-ane
-ene
-ol
-al
-one
-oic acid

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7
Q

Give the prefixes for:
CH3 group
C2H5 group
C3H7 group
C4H9 group
Cl group
Br group
I group

A

•Methyl-
•Ethyl-
•Propyl-
•Butyl-
•Chloro-
•Bromo-
•Iodo-

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8
Q

Define structural isomerism

A

When molecules have the same molecular formula but different structural formula

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9
Q

What is positional isomerism?

A

Functional group is attached to the main chain at a different place

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10
Q

What is functional group isomerism?

A

Same atoms but different functional group due to a different arrangement of atoms

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11
Q

What is a chain isomerism?

A

Hydrocarbon chain organised differently e.g branched chains

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12
Q

Define stereoisomerism

A

When molecules have the same structural and molecular formula, but have a different arrangement of atoms in space

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13
Q

What is E-Z isomerism?

A

Is caused by the limited rotation about c=c double bonds

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14
Q

How are E and Z isomers decided?

A

If the 2 substituents with the highest molecular formula mass are on same side of double bond, it is the Z (zusammen) isomer
If they’re on different sides it is the E (entgegen) isomer

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15
Q

What is an alkane?

A

A saturated hydrocarbons containing C-H bonds only

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16
Q

What’s the general formula of an alkane?

A

CnH2n+2

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17
Q

Are the bonds in alkanes polar/non polar? Why?

A

Non-polar: Carbon and hydrogen have similar electronegativities

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18
Q

Which intermolecular forces do alkanes have and why?

A

Only VDW forces of attraction as bonds are non-polar

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19
Q

Are alkanes soluble in water? Why?

A

Insoluble as hydrogen bonds in water are stronger than alkanes’ VDW forces of attraction

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20
Q

How reactive are alkanes?

A

Very unreactive

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21
Q

Which reactions will alkanes undergo?

A

Combustion and reaction with halogens

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22
Q

What is crude oil?

A

Mixture of fractions (hydrocarbons with similar boiling points and properties)

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23
Q

How is crude oil formed? Is it renewable?

A

Formed at high temps and pressures deep below earth’s surface over millions of years
Therefore non renewable

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24
Q

Name the fractions from high to low boiling points

A

Gases - fuel on site
Gasoline/petrol/naphtha - cars
Kerosene/paraffin - jet fuel, lighting
Diesel oil - lorries/taxis
Lubricating oil/waxes - candles, engine oil
Fuel oil - ships, power stations
Tar/bitumen - roads/roofing

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25
Q

What is fractional distillation?/how does it work?

A

crude oil heated until mostly vaporised
Passed into a fractionating tower thats cooler at top than the bottom
liquid fractions are piped off the at the bottom
Vapours rise up the column & -via trays&bubblecaps- condense when temp<their boiling point
Shortest chain hydrocarbons condense at top as they have lowest bpt

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26
Q

What is fracking and how is it done?

A

Natural gas held within shale rock
Drill into shale, force pressurised water and sand into rock to fracture it, collect gas
HCl and methanol added to break up shale and prevent corrosion

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27
Q

What are the advantages of fracking?

A

Gas supply for many years
Reduces imported gas and electricity

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28
Q

What are the disadvantages of fracking?

A

Lots of traffic to the local area
Concern about amount of water used
Chemical additives can pollute water supplies
Can cause small earthquakes
Combust CH4->CO2->global warming

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29
Q

Why are alkanes cracked?

A

To turn a long chain alkane (not economically viable) into a shorter chain alkane and an alkene (more reactive, starting point for many products)

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30
Q

Why is a shorter chain alkane more economically viable?

A

As they can be used as a fuel

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31
Q

What are the conditions for thermal cracking?

A

700-1200 K temperature
Up to 7000kPa pressure

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32
Q

What is the intermediate for the reaction?

A

Free radicals

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33
Q

What are the main products for thermal cracking?

A

alkenes

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34
Q

What are the conditions for catalytic cracking?

A

Lower temp (720K)
Lower pressure (but above atmospheric)
Zeolite catalyst (SiO2 and Al2O3) with a honeycomb structure to give a large surface area

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35
Q

What are the main products of catalytic cracking?

A

Cycloalkanes, aromatic hydrocarbons, branched alkanes

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36
Q

Write an equation for the combustion of propane

A

C3H8 + 5O2 —> 3CO2 + 4H2O

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37
Q

What is a fuel?

A

Something which releases heat energy when combusted

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38
Q

What are the 5 main fuels comprising of alkanes?

A

Methane, Butane, Propane, petrol (about C8), paraffin (C10-C18)

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39
Q

What is incomplete combustion? What products are formed in the case of alkanes?

A

Combustion in a limited supply of oxygen
CO - carbon monoxide- poisonous
C - carbon - soot - global dimming

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40
Q

Which type of hydrocarbons are most likely to undergo incomplete combustion?

A

Longer chains

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41
Q

What is the environmental impact of carbon monoxide?

A

It’s toxic/poisonous

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42
Q

What is the environmental impact of nitrogen oxides?

A

Forms nitric acid -> acid rain, photochemical smog

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43
Q

What is the environmental impact of sulfur impurities/ sulfur dioxide?

A

Forms sulphuric acid -> acid rain

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44
Q

What is the environmental impact of soot (carbon)?

A

asthma, global dimming, cancer

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45
Q

What is the environmental impact of unburnt hydrocarbons?

A

Photochemical smog

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46
Q

What is the environmental impact of carbon dioxide?

A

greenhouse gas-> global warming,
increases local temperatures,
speeds up climate change

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47
Q

What is the environmental impact of water vapour?

A

greenhouse gas-> global warming,
increases local temperatures,
speeds up climate change

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48
Q

What are flue gases?

A

Gases given out by power stations

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49
Q

Write 2 equations for 2 different ways of desulfurising flue gases

A

CaO(s)+2H2O(l)+SO2(g)+1/2O2(g)—> CaSO4 2H2O(s)
or
CaCO3(s)+SO2(g)+1/2O2(g)—> CaSO4+CO2(g)

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50
Q

What are catalytic converters made up of?

A

Ceramic honeycomb coated with platinum, palladium and rhodium metals

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51
Q

What do catalytic converters catalyse (equations)?

A

They catalyse these reactions of products from car exhausts
2CO(g)+2NO(g)—>N2(g)+2CO2(g)
Hydrocarbons+NO—>N2+CO2+H2O

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52
Q

What are greenhouse gases?

A

Gases which trap infrared radiation, making the earth act like a greenhouse

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53
Q

What is the greenhouse effect and how does it contribute to global warming?

A

Greenhouse gases trap infrared radiation in atmosphere, atmosphere heats up —> global warming

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54
Q

Define carbon neutral activities?

A

Activities that produce no net/overall carbon dioxide emissions

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55
Q

How are halogenoalkanes formed from alkanes?

A

Free radical substitution reaction

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56
Q

What are the 3 stages of free radical substitution?

A

•Initiation-breaking halogen bond to form free radicals
•Propagation-chain part of the reaction where products are formed but free radical remains
•Termination-free radicals removed, stable products formed

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57
Q

What are the conditions needed for the formation of a free radical chlorine atom?

A

Presence of UV light

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58
Q

Write equations for the reaction of CH4 with Cl2 to form CH3Cl

A

initiation:Cl2–>2Cl• (in presence of UV light)
propagation:Cl•+CH4–>HCl+•CH3
•CH3+Cl2–>CH3Cl+Cl•
Termination: •CH3+Cl•->CH3Cl
2Cl•->Cl2
•CH3+•CH3->CH3CH3

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59
Q

What is the ozone layer’s function?

A

Protects the earth from harmful exposure too too many UV rays

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60
Q

How do CFC’s break the ozone layer down?

A

Free radical substitution

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61
Q

Write an equation for the overall decomposition of ozone into oxygen (O2)

A

2O3 —> 3O2

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62
Q

Write free radical substitution equations to show how Cl free radicals catalyse the decomposition of O3

A

Cl2 -> 2Cl (in presence of UV light)
Cl•+O3 -> ClO•+O2
ClO•+O3 -> 2O2+Cl•
Overall: 2O3 -> 3O2

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63
Q

Are halogenoalkanes soluble in water?

A

Insoluble as C-H bonds are non-polar, not compensated for enough by C-X bond polarity

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64
Q

Do halogenoalkanes have a polar bond? Why?

A

Yes polar, as halogen has a higher electronegativity than C (halogen os delta-, Carbon is delta+)

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65
Q

Which intermolecular forces do halogenoalkanes have? Why?

A

Permanent dipole-dipole and VDW forces of attraction
C-X bond polarity creates permanent dipoles

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66
Q

When would halogenoalkanes have higher melting points?

A

Increase Carbon chain length
Halogen further down group 7

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67
Q

How would the mass of a haloalkane compare with the mass of an alkane of the same chain length?

A

Greater because mass of halogen > mass of H

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68
Q

What is the most important in determining haloalkanes reactivity?

A

Carbon-halogen bond enthalpy

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69
Q

What is the order of reactivity of halogenoalkanes?

A

Although C-F is most polar bond, the bond enthalpy of C-X decreases down the group so reactivity increases down the group

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70
Q

What is a nucleophile?

A

A negatively charged ion/delta- atom with a lone pair of electrons which can be donated to an electron deficient atom

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71
Q

Give 3 examples of nucleophiles

A

:OH-
:CN-
:NH3

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72
Q

What is nucleophilic substitution?

A

A reaction where a nucleophile donates a lone pair of electrons to delta+ C atom, delta- atom leaves molecule (replaced by nucleophiles)

73
Q

Draw the mechanism for the reaction of bromoethane with NaOH (aq)

A

H H
| |/\
H-C-C-Br
| | \
H H \ :OH-

74
Q

Draw the mechanism for the reaction of bromoethane with NH3

A

H H H H H
| |/\ | | |+
H-C-C-Br —> H-C-C-N-H /
| | \ | | | \/
H H \ :NH3 H H H

75
Q

What are CFC’s?

A

Chlorine-fluoro-carbons - haloalkanes containing C, F and Cl only (no H)

76
Q

What is the problem with CFC’s?

A

Although unreactive under normal conditions, they catalyse they catalyse the breakdown of ozone in the atmosphere via free radical substitution

77
Q

What are CFC’s being replaced with?

A

HCFC’s (hydrogen, chlorine, fluorine, carbon)
HFC’s (hydrogen, fluorine, carbon)

78
Q

What are the conditions/reactants needed for the elimination reaction of alkanes?

A

NaOH or KOH dissolved in ethanol (no water present)
Heated

79
Q

What is formed in the elimination reaction of haloalkanes?

A

An alkene, water and halogen ion

80
Q

What is an alkene?

A

Unsaturated bonds with a C=C double bond

81
Q

What is the general formula of an alkene?

A

CnH2n

82
Q

Why is there no rotation about the C=C double bond?

A

Due to the pi orbital - electron density above and below the single bond, which holds the carbon atoms in place

83
Q

Are alkenes more or less reactive than alkanes? Why?

A

More reactive due to high electron density of double bond and the fact the pi-bond is slightly easier to break

84
Q

What intermolecular forces of attraction do alkenes have?

A

Only VDW forces due to non-polar bonds

85
Q

Are alkenes soluble in water? Why?

A

No, non-polar bonds (VDW’s < hydrogen bonding)

86
Q

Name the 3 kinds of isomers alkenes have

A

Chain isomers (branched chains)
Position isomers (C=C on different Carbon atoms)
Geometric E-Z isomers

87
Q

Write an equation for the complete combustion of pent-2-ene

A

CH3CH=CHCH2CH3 + 7.5O2 —> 5CO2+5H2O

88
Q

What is an electrophile?

A

Electron deficient atoms/ions which accept a pair of electrons (here, from the C=C double bond)

89
Q

What is the most stable type of carbocation intermediate? Why?

A

Alkyl groups have a positive inductive effect,so the most stable carbonation is the one bonded to the most other carbon atoms (i.e tertiary carbocation)

90
Q

Major products will be formed from which kinds of carbocations?

A

Tertiary (or the most stable available)

91
Q

What conditions are needed for the electrophilic addition of H2O to an alkene?

A

Acid catalyst, usually phosphoric acid

92
Q

What are the products of the electrophilic addition of H2O to an alkene reaction?

A

An alcohol

93
Q

What conditions are needed for the electrophilic addition of a hydrogen halide to an alkene?

A

Room temperature

94
Q

What conditions are needed for the electrophilic addition of a halogen molecule to an alkene?

A

Room temperature and organic solvent

95
Q

How does a molecule with a non-polar bond react as if it is an electrophile?

A

C=C double bond with a high electron density induces a temporary dipole in the halogen molecule—>delta+ atom attracted to double bond

96
Q

How would you turn the product (from sulphuric acid+ethene) into an alcohol and how does this show that sulfuric acid catalyses the addition of water to an alkene?

A

Add water
H2SO4 reforms showing it catalyses the addition of alkenes

97
Q

What is an addition polymer?

A

Many monomers bonded together via rearrangement of bonds without the loss of any atom or molecule

98
Q

What are monomers? What form do they usually take?

A

Molecules which combine to form a polymer
Usually have a C=C bond which breaks to leave a repeating pattern

99
Q

Give 3 uses of poly(chloroethene)/PVC

A

Drainpipes
Vinyl
Aprons

100
Q

Give 2 examples of plasticisers

A

esters and phthalates

101
Q

What are plasticisers?

A

Small molecules that get between polymer chains to force them apart and allow them to slide over one another

102
Q

How do the physical properties of PVC change due to a plasticiser? What applications does this lead to?

A

PVC with a plasticiser becomes flexible , used for aprons
Without a plasticiser, PVC is rigid, used for drainpipes

103
Q

Why do things containing mainly C-C and C-H bonds not decompose easily?

A

Bonds are non-polar so are not attacked by enzymes

104
Q

Why is a lack of biodegradability in compounds with C-C or C-H bonds a problem?

A

Disposal is very problematic

105
Q

What is mechanical recycling?

A

Where plastics are separated into different types, washed, ground down, melted and re-moulded

106
Q

What is mechanical recycling used for?

A

Soft drinks bottles —> fleeces

107
Q

What is feedstock recycling?

A

Plastics heated to a temperature which break polymer bonds, leaving original monomers that can be made into new plastics

108
Q

What is feedstock recycling used for?

A

Making totally new plastics

109
Q

What is a problem with recycling?

A

Each time thermosoftening plastics are melted and remoulded, their properties degrade, so they can only be remoulded a limited number of times

110
Q

What is the functional group of an alcohol?

A

Hydroxyl group -OH

111
Q

What is the general formula of am alcohol?

A

CnH2n+1OH

112
Q

How do you name alcohols (one prefix, one suffix)?

A

Hydroxyl- or -OH

113
Q

What kind of intermolecular forces do alcohols have? Why?

A

Hydrogen bonding due to the electronegativity difference in the OH bond

114
Q

How do alcohols’ mpt and bpt compare to other hydrocarbons’ of similar C chain lengths? Why?

A

Higher, because they have hydrogen bonding—> Stronger than VDW forces

115
Q

Are alcohols soluble in water? Why does solubility depend on chain length?

A

Soluble when short chain - OH hydrogen bonds to hydrogen bond in water
Insoluble when long chain - non-polarity of C-H bonds take precedence

116
Q

What makes an alcohol primary?

A

C bonded to OH is only bonded to one other C atom

117
Q

What makes an alcohol secondary?

A

C bonded to OH is bonded to 2 other C atoms

118
Q

What makes an alcohol tertiary?

A

C bonded to OH is bonded to 3 other C atoms

119
Q

How can ethanol be made from crude oil?

A

Hydration of ethene via electrophilic addition (phosphoric acid catalyst H3PO4)

120
Q

What are the advantages and disadvantages of making ethanol from crude oil?

A

Advantages: fast,continuous process, ethanol has a high purity
Disadvantages: non renewable as from crude oil

121
Q

How can ethanol be made by fermentation?

A

Plant carbohydrates broken down and fermented by enzymes in yeast —> ethanol

122
Q

What conditions are needed for the reaction to make ethanol by fermentation?

A

Enzymes in yeast as a catalyst, 35°C, anaerobic conditions

123
Q

Write an equation for the reaction that takes place when ethanol is made by fermentation

A

C6H12O6(aq)—>2C2H5OH + 2CO2

124
Q

What are the advantages and disadvantages from making ethanol by fermentation?

A

Advantages: renewable as from plants
Disadvantages: slow,batch process, enzymes stop working at 15% alcohol so solution isn’t pure, needed to be fractionally distilled

125
Q

In the future, how might most ethene be made? Why isn’t it made like this at the moment?

A

Dehydrate ethanol made by fermentation —> ethene
Not economical at the moment

126
Q

Define carbon neutral

A

No net addition of CO2 to the atmosphere - CO2 released when combusted = CO2 absorbed as a plant

127
Q

Explain how using ethanol in petrol engines could be considered to be carbon neutral?

A

CO2 released in fermentation and combustion = CO2 absorbed when growing

128
Q

Why would it be probably not be entirely carbon neutral to use ethanol in petrol engines?

A

Other “carbon costs” associated with it eg transport

129
Q

What is a commercial fuel that uses ethanol? What else does it contain and why?

A

Methylated spirits - methanol (toxic so cant be drunk)

130
Q

Write an equation for the combustion of ethanol

A

C2H5OH(l)+3O2(g)—>2CO2(g)+3H2O(l)

131
Q

What is an elimination reaction?

A

The removal of a smaller molecule from a larger one

132
Q

Which group leaves the parent molecule in the case of alcohols?

A

OH and a H (to form water)

133
Q

What physical conditions are needed for the elimination reaction from alcohols to alkenes? (2 alternatives)

A

Excess hot concentrated sulphuric acid or pass vapour over hot aluminium oxide

134
Q

What forms if you partially oxidise a primary alcohol?

A

An aldehyde

135
Q

What conditions are needed to partially oxidise a primary alcohol?

A

Dilute sulphuric acid, potassium dichromate (VI), distill product as it’s produced, gentle heating

136
Q

Write an equation for the partial oxidation of ethanol

A

CH3CH2OH(l)+[O]—>CH3CHO(g)+H2O(l)

137
Q

What forms if you fully oxidise a primary alcohol?

A

A carboxylic acid

138
Q

What conditions are needed to fully oxidise a primary alcohol?

A

Concentrated sulphuric acid, potassium dichromate (VI), reflux for about 20 mins, strong heating

139
Q

Write an equation for the full oxidation of ethanol

A

CH3CH2OH(l)+2[O]—>CH3COOH(g)+H2O(l)

140
Q

What forms if you oxidise a secondary alcohol?

A

A ketone

141
Q

Why can alcohols not be oxidised further and why cant tertiary alcohols be oxidised?

A

A carbon-carbon bond would have to break

142
Q

What conditions are needed for the oxidation of a secondary alcohol?

A

Concentrated sulphuric acid, potassium dichromate (VI), reflux about 20 mins, strong heating

143
Q

Write an equation for the oxidation of propan-2-ol

A

CH3CH(OH)CH3(l)+[O]—> CH3COCH3(g)+H2O(l)

144
Q

What is an aldehyde? What is its functional group?

A

Molecule with C=O group at the end of a carbon chain, carbonyl functional group (C=O)

145
Q

How do you name aldehydes? Give an example

A

Suffix -al
eg. ethanal

146
Q

What is a ketone? What is its functional group?

A

Molecule with C=O group in the middle of a carbon chain, carbonyl functional group (C=O)

147
Q

How do you name ketones? Give an example?

A

Suffix -one
eg. propanone

148
Q

What is a carboxylic acid? What is its functional group?

A

Molecule with a COOH group, which has to be at the end of a carbon chain
Carboxyl functional group (made up of a carbonyl C=O and hydroxyl -OH group)

149
Q

How do you name carboxylic acids? Give an example?

A

Suffix -oic acid
eg. propanoic acid

150
Q

What does the Tollens’ test give a positive result for?

A

Aldehydes

151
Q

What is in Tollens’ reagent? How does this react with the substance to be tested?

A

Silver nitrate in NH3 (aq) - oxidises aldehydes but not ketones
Complex silver (l) ions reduced to Ag(s)

152
Q

How do you carry out the Tollens’ test?

A

Add equal volumes of substance being tested and tollen’s reagent to a test tube, leave in water bath for 10 mins and observe any changes

153
Q

What is the result of the Tollen’s test for aldehydes and ketones?

A

Aldehydes - silver mirror forms (solid Ag)
Ketones - no visible change

154
Q

What does Fehling’s solution give a positive result for?

A

Aldehydes

155
Q

What is in Fehling’s? How does this react with the substance to be tested?

A

Blue copper (II) complex ions - gentle oxidising agent
Reduced to Cu+ ions (brick red)

156
Q

What conditions do you need to use the Fehling’s solution?

A

Heat

157
Q

What result do aldehydes and ketones give in the Fehling’s test?

A

Aldehydes - brick red ppt
Ketones - no visible change

158
Q

How do you test for alkenes? What is the result?

A

Shake with bromine water, result is bromine water is decolourised (orange to colourless)

159
Q

How do you test for haloalkanes? What is the result?

A

Add NaOH(aq) and warm, acidify with HNO3, add AgNO3(aq)
Result: precipitate of AgX (for Cl=white, for Br=cream, for I=yellow)

160
Q

How do you test for alcohols? What is the result?

A

Add acidified K2Cr2O7 (potassium dichromate (VI)) and heat
Result: colour change from orange to green for primary and secondary alcohols (no change for tertiary alcohols)

161
Q

How do you test for aldehydes? What is the result? (2 ways)

A
  1. Warm with Fehling’s solution, result: brick red ppt forms (from blue solution)
  2. Warm with Tollen’s reagent, result: “silver mirror” (Ag(s) ppt) forms
162
Q

How do you test for carboxylic acids? What is the result?

A

Add NaCO3 (aq), result: CO2 (g) given off - effervescence

163
Q

What is mass spectrometry? How does it work?

A

Used to find RMM of organic compounds
Compound is dissolved in solution, ionised by high voltage supply (to mostly 1+ ions), accelerated by a negatively charged plate, becomes beam of ionised molecules, reach detector&cause a current to flight. ToF used to work out m/z value and plot a graph

164
Q

What does the x axis show on a mass spectrum? What does this effectively show and why?

A

Shows m/z value (mass divided by ionic charge)
Since most ions are 1+, this effectively shows Mr

165
Q

Why are there multiple peaks when molecules are put into a mass spectrometer?

A

The molecular ion is shown as a peak, but it will also fragment into smaller molecules, so these peaks are shown as well
Also, due to isotopes of atoms, different peaks may be seen

166
Q

How does chromatography work and what does it tell you?

A

A stream of gas carries a mixture of vapours through a column packed with solids, different compounds move through different speeds, so they’re separated. The amount of each compound can then be measured

167
Q

What does GCMS stand for?

A

Gas chromatography linked to mass spectrometry

168
Q

What might GCMS be used for?

A

Powerful chemical analysis - forensic work, measuring water pollution, drug testing on athletes, racehorses

169
Q

What is high resolution mass spectrometry?

A

Mass spectrometers which give Mr to 3dp or 4dp are called high resolution (low resolution is given to nearest whole number)

170
Q

What does a high resolution mass spectrometer allow you to do?

A

Distinguish between compounds that have the same Mr to nearest whole number, but are made up of different atoms and so have different values of Mr to 3dp

171
Q

Why do atoms and chemical bonds absorb infrared radiation?

A

They’re constantly vibrating - they can absorb infrared radiation that’s the same frequency as their frequency of vibration

172
Q

What effect does a stronger bond have on the frequency of vibration?

A

Vibrate faster (with higher frequency)

173
Q

What effect do heavier atoms have on frequency of vibration?

A

Vibrate slower (with lower frequency)

174
Q

How does infrared spectroscopy work?

A

Every bond has a unique vibration frequency in the infrared region of the EM spectrum.
Bonds absorb radiation that has the same frequency as their frequency of vibration.
Infrared radiation emerged from a sample is missing the frequencies that have been absorbed (info can be used to identify the compounds functional group)

175
Q

What happens inside an infrared spectrometer?

A

Beam of infrared radiation with a range of frequencies is passed through a sample
Radiation that emerges is missing frequencies that have been absorbed by the bonds in the sample
Graph is plotted of intensity against frequency of radiation

176
Q

What do the troughs on an infrared spectrum show?

A

The frequencies where radiation has been absorbed - match to table to find out which bonds they represent

177
Q

What is the fingerprint region?

A

Area on the infrared spectrum below wavenumber of 1500cm-1
Many peaks, caused by complex vibrations of the whole molecule. Unique to every compound, so can be used to identify compounds

178
Q

How is the fingerprint region used to identify compounds?

A

The fingerprint region’s pattern is matched to a database on a computer to identify the compound accurately

A level Chemistry (11 decks)

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