Unit 4 AOS 1 Flashcards Preview

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Flashcards in Unit 4 AOS 1 Deck (293):
1

What is the valency of the Carbon atom

4

2

How many outer shell electrons does carbon have

4

3

Nature of C-C bond

strong and stable

4

Prefixes for halogens

chloro, idodo, bromo, fluoro

5

What is the functional group for ketones

carbonyl group

6

How do you label an alkene/alkyne with more than one bond

di, tri, tetra

7

What can't C=C bonds do

rotate

8

What are the groups called for trans and cis isomers

hetero groups

9

What does it mean if you can draw a line of symmetry in compound

it's achiral

10

What reactions can alkenes undergo

substitution, photochemical substitution

11

What is photochemical substitution equation for with Cl

alkane + Cl (UV) = haloalkane + HCl

12

What should be added to hydrocarbon to form amino group

ammonia

13

Formula for ammonia

NH3

14

What happens when you add water to alkene + catalyst

OH and H are added into hydrocarbon

15

What type of catalyst is necessary for addition of water to alkene

acidic catalyst

16

What is needed to react H2 with alkene

catalyst, e.g. Pt

17

What reaction can a secondary alcohol undergo

oxidation to form ketone

18

What reactions can a primary alcohol undergo

oxidation to form aldehyde, esterification

19

What reactions can a carboxylic acid undergo

can be reacted with amine to form amide and water, esterification

20

What can't tertiary alcohols react to form

ketone, aldehyde, carboxylic acid

21

What is needed for esterification to occur

concentrated H2SO4 (liquid) and all of the reactants must be in liquid state

22

What is necessary for hydrolysis of an ester

water, H+

23

What is organic chemistry

study of carbon-containing compounds (usually containing C-H bonds and excluding compounds such as cyanide, carbon oxides and carbonates - as they are inorganic compounds)

24

What are hydrocarbons

compounds containing only carbon and hydrogen atoms

25

Explanation for covalent bonds in carbon

The electronegativity of carbon is too low for a carbon to attract electrons from another element to form a negative ion and it is too high to release electrons to another element to form a positive ion

26

What are covalent bonds

Bonds between two or more non-metal atoms involving the sharing of electron pairs between atoms.

27

Are carbon compounds relatively stable

yes

28

Why can carbon form double bonds/rings

they are of a small size so can get close enough

29

Why can carbon form bonds and chains of various lengths

covalent bonds with self

30

Second best atom for this

silicon

31

Why are carbon compounds diverse

because can form 4 bonds

32

What is bond energy

the measure of the amount of energy needed to break apart 1 mole of covalently bonded molecules in the gaseous state

33

Why organic chemistry is important

drugs/medicine, agriculture, industrial applications

34

What are natural compounds

carbohydrates, protein, fats/oils, hydrocarbons, enzymes, vitamines, alkaloids

35

What are carbohydrates needed for

source of energy in food

36

What are proteins needed for

source of compounds for growth and repair of tissues in body

37

What are the applications of fats and oils/role in the body

source of energy found in food, stored in body, used in cooking, soaps

38

hat are Hydrocarbons used for

fuels, petrol, cooking

39

What are enzymes

complex protein molecules found in plants and animals, catalysis of biochemical reactions

40

Where are alkaloids found

found in variety of compounds including medicines

41

Synthetic compounds examples

soaps/detergents, antibiotics, polymers

42

What are aliphatic compounds

Describes organic compounds in which carbon atoms form open chains.

43

Aromatic compounds

Describes a compound that contains at least one benzene ring and is characterised by the presence of alternating double bonds within the ring.

44

Alkanes

saturated, simple carbon compounds containing only single bonds

45

General formula for Alkanes

CnHn+2

46

Saturated hydrocarbons

Hydrocarbons containing only single carbon–carbon bonds and they cannot take up any more hydrogens.

47

Unsaturated hydrocarbons

Hydrocarbons containing at least one double carbon–carbon bond.

48

Bond angle of methane

109.5 degrees

49

Homologous series

A series of organic compounds that have the same structure but in which the formula of each molecule differs from the next by a CH2 group.

50

Use of methane

fuel

51

Use of ethane

manufacture of ethene

52

Use of propane

fuel, aerosols

53

Use of butane

fuel, aerosols

54

Formulas in which compounds can be written

molecular, empirical, structural, semi-structural/condensed, skeletal, 3D structural

55

Structural isomers

Molecules that have the same molecular formula but different structural formulas.

56

Alkenes

The family of hydrocarbons that contain one carbon–carbon double bond.

57

What is ethene known as

ethylene

58

Alkynes

The family of hydrocarbons with one carbon–carbon triple bond.

59

Cyclohexane

A pungent saturated cyclic hydrocarbon C6H12 found in petroleum.

60

General formula of cycloalkanes

CnH2n.

61

Aliphatic compound example

cycloalkanes

62

Benzene

An aromatic hydrocarbon with the formula C6H6. Lack of reactivity, high stability and same bond lengths between the carbon atoms.

63

Benzene is used for

used to produce food, pharmaceuticals but is carcinogenic

64

Simplest homologous series

alkanes

65

Functional group

- group of atoms attached to or part of a hydrocarbon chain that influence the physical and chemical properties of the molecule. Determines function of compound.

66

Is a compound with or without a functional group more stable

without as if a functional group is attached, it is more likely to react

67

Do compounds with functional groups form a homologous series

yes

68

Hydroxyl group

OH functional group

69

Alcohols/alkanols

hydrocarbons containing the OH functional group

70

Carboxyl group

the COOH functional group, which has weakly acidic properties.

71

Carboxylic acids

Hydrocarbons containing the COOH functional group

72

Alcohol functional group

hydroxyl

73

Alcohol suffix

ol

74

Aldehyde functional group

aldehyde (HC=O)

75

Aldehyde suffix

al

76

Ketone functional group

carbonyl (C=O)

77

Ketone suffix

one

78

Carboxylic acid functional group

carboxyl (COOH)

79

Carboxylic acid suffix

oic acid

80

Ester functional group

ester (OCO)

81

Ester suffix

alkyl alkanoate (alcohol carboxylic acid)

82

Ether functional group

ether (R-O-R)

83

Amine functional group

amine/amino NH2

84

Amine suffix

amine

85

Amide functional group

amide (O=CNH2)

86

Amide suffix

amide

87

Primary alcohol

C-OH is attached to one other carbon atom

88

Secondary alcohol

C-OH is attached to two other carbon atoms

89

Tertiary alcohol

C-OH is attached to three other carbon atoms

90

What is a property aldehydes are known for

smell

91

What do the low molecular weight aldehydes smell like

unpleasant

92

What do high molecular weight aldehydes smell like

pleasant

93

Uses of aldehydes

perfumes, solvents, manufacture of plastic, dyes, pharmaceuticals

94

Uses of carboxylic acids

making soaps and polyesters, found in foods

95

Ester

An organic compound formed from a condensation reaction between an alcohol and a carboxylic acid.

96

Ester is used in

paints, perfumes, cosmetics, artificial flavourings found in fruits

97

Primary, secondary and tertiary amines determined by

how many C connected to N

98

Amine called ... if high functional group

amino if higher functional group

99

Amide uses

solvents in a variety of pharmaceuticals, creating nylon and other polymers, to colour crayons/pencils

100

Priority for naming scale

carboxylic acid > ester > amide > aldehyde > ketone > alcohol > amine > alkyne=alkene > alkane

101

Organic reactions

reactions that take place between organic compounds

102

Types of organic reactions

Addition, decomposition, combination, substitution, rearrangement

103

3 types of intermolecular forces

dispersion forces, dipole-dipole attractions and hydrogen bonding

104

What are physical properties affected by

size, shape structure and degree of polarisation of molecules

105

Simple organic compounds are generally (what state)

gases, volatile liquids or solids with low melting and boiling points (because intermolecular forces are weak)

106

What is the strength of dispersion forces affected by

shape and size of molecules

107

Isomers

two or more compounds with the same molecular formula but different arrangements of atoms

108

Structural isomers

Molecules that have the same molecular formula but different structural formulas.

109

When do isomers have different physical and chemical properties

when different functional group

110

Why do isomers have different physical and chemical properties when there is a different functional group

Functional isomers have different intermolecular forces and distinctly different properties.

111

Three types of structural isomers

chain isomers, positional isomers, functional isomerism.

112

Chain isomer

A type of structural isomer that involves more branching.
In chain isomers, more branched isomers have lower boiling points. Could be because more spherical and has less surface area for the dispersions forces to act.

113

Positional isomers

Isomers where the position of the functional group differentiates the compounds.

114

What does the position of the functional group affect

compactness and polarity

115

Functional isomers

Isomers containing different functional groups.

116

Stereoisomers

Two or more compounds differing only in the spatial arrangements of their atoms. The atoms are connected in the same order but are oriented differently in space

117

Types of stereoisomers

cis and trans isomers, enantiomers or optical isomers

118

Cis-trans isomers

types of stereoisomers that are formed when the same two different groups are bonded to each of the carbon atoms in a carbon-carbon double bond. A cis isomer has identical groups on the same side of the double bond; a trans isomer has the groups on opposite sides.

119

Is cis or trans stronger

cis (e.g  in trans the dipoles may cancel out)

120

Does trans or case have higher boiling points

cis is higher

121

Does trans or cis have a higher melting point

trans is higher as they can pack more closely

122

Can trans and cis occur in rings

yes

123

Chiral

Describes compounds containing an asymmetric carbon atom or chiral centre. The molecule cannot be superimposed upon its mirror image.

124

Chiral centre

An asymmetric carbon atom.

125

Enantiomers

Chiral molecules that are non-superimposable mirror images of one another.

126

Are enantiomers symmetrical

no

127

Are the physical/chemical properties the same for enantiomers

physical properties are identical (except for optical activity) and their chemical properties are generally the same, but they react differently with other molecules that have optical properties.

128

What it’s called when it’s not chiral

achiral

129

What is necessary for something to be achiral

2 or more groups attached to tetrahedral are the same

130

What are the states of alkanes

first 4 are gases, because as the size of the molecule increases, so does the influence of the dispersion forces; therefore, the melting and boiling points increase.

131

What affects boiling point

dispersion forces, degree of branching

132

Does branching increase or decrease boiling points

decrease due to the inability of molecules to get closer to each other; as the dispersion forces operate over a small distance only, the attraction is diminished.

133

What is viscosity

A measure of a fluid’s resistance to flow

134

The viscosity of liquid alkanes increases with…

the number of carbon atoms

135

What increases viscosity

n.o. intermolecular forces, branched molecules becoming tangled

136

What happens to viscosity as temp increases

decreases because have enough energy to overcome forces

137

What is flashpoint

The temperature at which a particular organic compound gives off sufficient vapour to ignite in air. Of volatile liquid is the lowest temperature at which the liquid gives off enough vapour to start burning at its surface on application of an ignition source. Below the flashpoint, there is not enough vapour available to support combustion.

138

What is a flammable liquid

is any liquid with a flashpoint below 38.7 degrees

139

Liquids classified as combustible are (in terms of if they are flammable or not and why)

harder to ignite and have a flashpoint of 37.8 and above
At what temperatures do flammable liquids ignite and burn easily - at lower temperatures. Combustible liquids can burn at temperatures that are usually above room temperature. It is not actually the liquid that burns; it is the mixture of its vapours that burns in the oxygen in the air.

140

Do smaller hydrocarbons have high or low flashpoint

low, as have weaker bonds and are more flammable

141

Are alkanes or alkenes more reactive

alkenes due to double bond

142

Are alkynes generally flammable

yes

143

What does adding halogen do to strength/polarity

more polar, stronger bonds.

144

Why do alcohols have higher boiling points than alkanes

OH group so hydrogen bonding + dipole-dipole

145

Are alcohols soluble in water

smaller ones are

146

Does alcohol boiling point increase with n.o. carbons

yes because of dispersion forces

147

Does solubility of alcohol increase with n.o. of carbons

no due to more non-polar sections of the molecules

148

Are alcohols highly flammable

yes

149

Do volatility/flammability decrease as the alcohol molecules increases

The flammability of alcohols decreases as the molecules increase in size and mass due to the increased strength of attraction between the molecules. Volatility also decreases as the size of the molecule increases.

150

Are carboxylic acids soluble

first are very soluble due to hydrogen bonding,

151

Do carboxylic acids or alcohols have higher boiling points

carboxylic acids due to more hydrogen bonding

152

Are carboxylic acids strong/weak acids

weak as they only partially ionise

153

Are aldehydes and ketones volatile

yes (no hydrogen bonds)

154

Does solubility increase with ketones and aldehydes with n.o carbon

no

155

Do esters have a higher booing point than carboxylic acids

no as they cannot form hydrogen bonds with each other as there is no OH bond

156

Does solubility increase with carbon n.o.

no

157

Are amines weak or strong acids or bases

weak base

158

Do amines have a higher boiling point than alcohol

no

159

What is states of amine

first 2 are gases, rest are liquids

160

Does solubility increase with carbon n.o.

no

161

Alkanes are fairly...

un-reactive: they do not dissolve in water, nor react with acids/bases

162

Substitution reaction

Reactions in which one or more atoms of a molecule are replaced by different atoms.

163

What is cracking

The process of breaking down complex chemical compounds by heating them. A process that uses heat and pressure, and sometimes a catalyst, to break larger hydrocarbon molecules into smaller molecules, including an alkene and hydrogen, or an alkane.

164

What are addition reactions

Reactions in which one molecule bonds covalently with another molecule without losing any other atoms. In addition reactions for alkenes, the double bond is broken, and new single bonds are formed. This is because the energy required to break the double bond is less than the energy released in the formation of two single bonds.

165

How to test for unsaturation

add bromine to alkene

166

What is needed to make ethene into ethanol

ethene + steam (H2O) = ethanol

167

What is polymerisation

A process of reacting monomer molecules together in a chemical reaction to form polymer chains.

168

What is a monomer

A molecule that links with other monomers to form a polymer.

169

How to form polyethene

use addition polymerisation of ethene

170

What is addition polymerisation

The process in which monomers with at least one double bond react together to form a polymer by addition reactions.

171

What is a polymer

Giant molecules formed by repeated monomers that have been joined by covalent bonds.

172

Acidified permanganate formula

H+/MNO4- (aq)

173

Acidified dichromate formula

H+/Cr2O72- (aq)

174

O2 (with a catalyst) can be added to alcohols to form

carboxylic acids and H2O is formed as a product

175

What are condensation reactions

Reactions in which molecules react and link together by covalent bonding with the elimination of a small molecule, such as water or hydrogen chloride, from the bond that is formed.

176

Polyesters are formed as a result of

ester linkages between monomers to form the polymer. In the formation of a polyesters, water is removed for every monomer (except for one water). Not necessarily ester monomer, just bonding.

177

% yield formlula

% yield = mass of product/theoretical mass * 100

178

Atom economy is

method for measuring the efficiency of a reaction that takes into account the amount of waste produced. The atom economy of a reaction considers the amount of useful product produced from a particular amount of reactants.

179

% atom economy formula

% atom economy = mass of atoms in desired product/mass of atoms in reactants X 100

180

What is chromatography used for

to separate the components of a mixture and to identify the components

181

What is qualitative analysis

An investigation used to identify the presence or absence of elements, ions or molecules in a sample. (What is in a substance)

182

What is quantitative analysis

An investigation used to determine the amount of a given element or compound.

183

What is spectroscopy

The investigation and measurement of spectra produced when matter interacts with or emits electromagnetic radiation.

184

Types of spectroscopy

mass spectrometry, NMR spectroscopy, IR spectroscopy

185

What is mass spectrometry

The investigation and measurement of the masses of isotopes, molecules and molecular fragments by ionising them and determining their trajectories in electric and magnetic fields.

186

What happens in mass spectrometry

molecules are bombard with high-energy electrons causing them to fragment and lose electrons, resulting in positive ions formed

187

Base peak

The most abundant/common ion in a mass spectrum - assigned a height of 100 - highest on the graph

188

Why is it the most common

most stable or can be formed in different ways

189

If there is a mass of 15 what is the fragment likely to be

methyl group

190

What is infrared spectroscopy

Describes spectroscopy that deals with the infrared region of the electromagnetic spectrum.

191

Do all objects emit IR radiation

yes

192

Why is infrared radiation used

as it is either emitted or absorbed by molecules when the bonds change their vibrational movements

193

What happens to the vibrational energy during IR spectroscopy

goes from the ground state to the excited state. A molecule can move from a lower to a higher vibrational energy level if it absorbs an amount of energy equal to the difference between levels.

194

What happens to the wave number as the wave length increases

it decreases

195

The more complicated the region on IR below 1000cm-1…

the more complex the molecule

196

Why is there a CH2 group near the OH in ethanol

because the OH is pulling it towards itself

197

What does NMR stand for

nuclear magnetic resonance

198

What two compounds can be used in NMR

13C and 1H

199

What happens when an external magnetic field is applied

the spinning nuclei either align with the external field or align against it

200

Which one has the higher energy level (either with or against)

against

201

What does applying radio waves do

causes the nucleus to flip which releases energy

202

Basis of NMR

the amount of energy required to change its spin state depends on the environment type

203

Main types of NMR

carbon-13 NMR, low-resolution proton NMR (H1), high-resolution proton NMR (H1)

204

What does TMS stand for

tetramethylsilane (CH3)4Si

205

Is NMR quantitative or qualitative

qualitative

206

What does the number of peak sets tell us

the number of unique environments

207

What does the chemical shift tell us

information about the functional groups involved

208

What does the n.o of sub-peaks/area under peak set tell us

n.o of H present in neighbouring environments

209

What is the scale for 13CNMR

0-250ppm

210

What is the scale for 1HNMR

0-13ppm

211

What is it called when you analyse relative area under each peak set

integral trace

212

Rule to determine n.o of H in adjacent environment

n+1 rule

213

What does HPLC stand for

high performance liquid chromatography

214

What is the mobile phase

The liquid or gas that flows through a chromatography system, moving the materials to be separated at different rates over the stationary phase.

215

What is the stationary phase -

A solid with a high surface area, or a finely divided solid coated with liquid. It shows different affinities for various components of a sample mixture when separating them by chromatography.

216

What is used in paper chromatography

usually cellulose or filter paper covered with water or ethanol

217

What is used in thin-layer chromatography

finely divided adsorbent material is coated onto either a glass slide or aluminium foil to form stationary phase and liquids are used for mobile phase

218

What is adsorption

The adhesion of atoms, ions or molecules from a gas, liquid or dissolved solid to a surface.

219

What is desorption

The removal of a substance from or through a surface; the opposite of adsorption.

220

What is generally used as a stationary phase for HPLC

narrow column that is packed tightly with a finely divided powder (high SA)

221

Examples of powders used

alumina or silica

222

What is an eluent

A substance used as a solvent in separating materials.

223

What is a sample

what is being analysed

224

What are analytes

The components of a sample.

225

What is retention time

The time taken for each component of a sample to travel from the injection port to the end of the column.

226

Area under each peak shows…

amount/concentration of substance

227

Normal-phase liquid chromatography

mobile phase is non-polar and stationary phase is polar

228

Reverse-phase liquid chromatography

mobile phase is polar and stationary phase is non-polar

229

What is most commonly used in HPLC

reverse-phase

230

What are the axes for calibration curve

peak area is the y axis and concentration is the x axis

231

What is likely to be compound if it evolves H2 when mixed with Mg

carboxylic acid

232

Volumetric analysis

Determination of the concentration, by volume, of a substance in a solution, such as by titration. Quantitative analysis.

233

pH formula

pH = -log10[H3O+] concentration

234

Hydronium/OH formula

[H3O+]*[OH-]=Kw where Kw = 1.0*10^-14

235

What is a pipette

instrument used to accurately measure or transfer small quantities of liquid

236

What is the aliquot

unknown concentration

237

What is the titrant

solution of known concentration

238

What is the burette

A graduated glass tube for delivering known volumes of a liquid, especially in titrations.

239

What is titration

Process used to determine the concentration of a substance by using a pipette to deliver one substance and a burette to deliver another substance until they have reacted exactly in their mole ratios.

240

What is the titre

The volume delivered by a burette.

241

2 types of titration

acid-base and redox

242

What is the standard solution

A solution that has a precisely known concentration.

243

What are the two methods of determining the concentration

reacting it with other solution whose concentration is known accurately (standardisation) or dissolving a primary standard into a known volume of water

244

What is the primary standard

A substance used in volumetric analysis that is of such high purity and stability that it can be used to prepare a solution of accurately known concentration.

245

Primary standards must be...

abundant, accurately known formula, high state of purity, cheap and readily available, relatively high molar mass,

246

Why shouldn’t NaOH be used

absorbs moisture, reacts with CO2

247

Why shouldn’t hydrated sodium carbonate

unsuitable as it loses water to atmosphere but can be heated to remove water then used

248

What is the volumetric flask used to contain

primary standard

249

What is the equivalence point

Where two reactants have reacted in their correct mole proportions in a titration.

250

What is the end point

The experimentally determined/approximated equivalence point at which the indicator just changes colour or the pH curve becomes vertical. Occurs after slight excess.

251

Titration curve

Curve used to measure the volume of a titrant against pH.

252

Concordant titres

Describes titres that are within a defined volume of each other, such as 0.10 mL.

253

Concentration formula using mol and volume

n=cV

254

Concentration formula using volumes

c1V1=c2v2

255

What is a diprotic acid

can donate 2 protons

256

What is a monoprotic acid

can donate 1 proton

257

What is a polyprotic acid

can donate more than 2 protons

258

What is an amphiprotic acid

can donate or accept protons

259

What is the retention time for large molecules

higher retention time

260

What is the retention for molecules that are soluble in mobile phase

shorter retention time

261

What are the axes for chromatogram

y axis is absorbance and x axis is retention time in minutes

262

What does elution rate mean

how fast it is passed out of column

263

Order of elution in normal phase in order of first elution to last

alkanes/alkenes, esters, alkyl halides, alcohols, carboxylic acids. It also goes shortest chain to longest chain.

264

What is the wavelength symbol

ʎ m

265

What is the wavelength in terms of the graph

the period of the graph

266

What is wave number proportional to

frequency

267

What happens if the frequency increases

the wavelength decreases and the energy of a photon increases

268

Formula for wave number

wavenumber = 1/wavelengthcm-1

269

What do large wavelengths mean

small wave numbers

270

What is the absorbance relative to

the concentration

271

Formula for delta E for NMR

delta E = hv where hv is radio energy

272

In NMR where is polar and where is shield thickness

low energy and polar is the left and left to right is decreasing shield thickness

273

What shape is the titration curve

S-shaped

274

Why is no indicator required for redox titration

as there is usually a colour change

275

What are the axes for IR

the y axis is transmittance and the x axis is the wave number

276

What are the names for the number of sub-peaks in NMR

singlet, doublet, triplet, quartet,

277

Formula for Rf

Rf=distance travelled by component/distance travelled by solvent

278

What does Rf stand for

retardation factor

279

What are the units for Rf

no units

280

What will titration curve look life for strong acid-weak base titration

fairly spread out titration S-shaped curve

281

What will titration curve look life for weak-acid strong base titration

very un-spread out (vertically)

282

What does strong acid and strong base form + pH

extremely weak conjugate base and extremely weak conjugate acid - pH of 7

283

What does strong acid and weak base form + pH

extremely weak conjugate base and weak conjugate base - pH is over 7

284

What does weak acid and strong base form

extremely weak conjugate acid and weak conjugate acid - pH less than 7

285

What is the tallest peak called in mass spectroscopy

base peak

286

What does the parent ion/peak tell us in mass spectroscopy

the molecular mass

287

What is the charge for all the ions on mass spectrum

+ 1

288

What does IR show

functional groups

289

Basis of IR

amount of IR absorbed depends on type of bond

290

What is the wave length for stronger bonds

higher wave length

291

What does the mass spectroscopy tell us

molecular formula

292

What is high resolution NMR

when it has sub-peaks that tell you n.o of H

293

What is low resolution NMR

no sub peaks