Artwork for Chem Ideas

8/9/2019 Artwork for Chem Ideas

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Figure 3 If the 6.02 x 10 23 atoms in 12 g of

carbon were turned into marbles, the marbles

could cover Great Britain to a depth of 1500 km!

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Figure 3 The mass spectrometer.

Figure 3 The mass spectrometer.

Figure 7 Variation of first ionisation enthalpy

with atomic number for elements with atomic

numbers 1 to 56.

Figure 8 Successive ionisation enthalpies

for aluminium.

sample inlet

electron gun

magnetic field

(at right anglesto paper)

ion detector

ionisation chamber

accelerating electric field

heavy particles

intermediate

particles

lighter particles

pump maintains

low pressure

He

Li

Ne

Na

Ar

K

Kr

Rb

Xe

Cs

2500

2000

1500

1000

500

Atomic number

50403010 200 I

o n i s a t i o n e n t h a l p y /

k J m o l – 1

Ionisation1st 2nd 3rd 4th 5th 6th 7th 8th

20 000

10 000

0 I o n i s a t i o

n e n t h a l p y / k J m o l – 1

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Figure 9 Successive ionisation enthalpies

for phosphorus.

Energy

Shell Sub-shell

n= 4

n= 3

n= 2

n= 1

444343

3

22

1

f dpdsp

s

sp

s

Figure 10 Energies of electron sub-shells from

n = 1 to n = 4 in a typical many-electron atom.

The energy of a sub-shell is not fixed, but falls as

the charge on the nucleus increases as you go

from one element to the next in the Periodic

Table. The order shown in the diagram is correct

for the elements in Period 3 and up to nickel in

Period 4. After nickel the 3d sub-shell has lower energy than 4s.

1s

2s

3s

3p

2p

3d

Energy

Figure 13 Arrangement of electrons in atomic

orbitals in a ground state sodium atom.

Ionisation1st 2nd 3rd 4th 5th 6th 7th 8th

20 000

10 000

0 I o n i s a t i o n e n t h a l p y / k J m o l –

1

30 000

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F i g u r e 1 4

B u i l d i n g u p t h e P e r i o d i c T a b l e .

s y m b

o l

e l e c t r o n i c c o n f i g u r a t i o n

( o u t e r s u b - s h e l l ( s ) o n l y )

a t o m i c

n u m b e r

K E Y O

8

2 p

4

A c t i n i d e s

L a n t h a n i d e s

P a

N p

P r

T h

U

C e

N d

P m

A c

F r

R a

5 8

5 9

6 0

6 1

9 0

9 1

9 2

9 3

8 7

8 8

8

9

4 5 6 7

3 d

1 4 s

2

3 d

3 4 s

2

4 d 1 5 s

2

4 d 3 5 s

2

5 d

1 6 s

2

5 d

3 6 s

2

3 d

2 4 s

2

3 d

5 4 s

1

4 d 2 5 s

2

4 d 5 5 s

2

5 d

2 6 s

2

5 d

4 6 s

2

4 s

1

5 s

1

6 s

1

7 s

1

4 s

2

5 s

2

6 s

2

7 s

2

4 d 5 5 s

1

3 d

5 4 s

2

5 d

5 6 s

2

3 1 1

1 9

4 1 2

2 0

3 7

5 5

3 8

5 6

2 3

2 5

2

1

3

9

5

7

2 4

4 1

2 2

4 0

7 2

4 3

4 2

7 3

7 5

7 4

L i

B e

N a

M g

K

C a

R b

S r

C s

B a

L a S

c Y

H f

T i

Z r

T a V N

b

W C r

M o

R e

M n

T c

f i l l i n

g d s u b - s h e l l s

f i l l i n g 4 f s u b - s h e l l

f i l l i n g 5 f s u b - s h e l l

3 d

6 4 s

2

4 d 7 5 s

1

5 d

6 6 s

2

3 d

7 4 s

2

4 d 8 5 s

1

5 d

7 6 s

2

3 d

8 4 s

2

5 d

9 6 s

1

3 d 1

0 4 s

1

4 d 1

0 5 s

1

5 d 1

0 6 s

1

3 d

1 0 4 s

2

4 d 1 0 5 s

2

5 d

1 0 6 s

2

2 7

2 9

2 8

4 5

2 6

4 4

7 6

4 7

4 6

7 7

7 9

7 8

3 0

4 8

8 0

6 3

6 2

9 4

6 5

6 4

9 5

9 7

9 6

6 6

9 8

A m

B k

E u

P u

C m

S m

G d

T b

O s

F e

R u

I r C o

R h

P t

N i

P d

A u

C u

A g

C f

D y

H g

Z n

C d

4 d 1 0 5 s

0

4 p

1

5 p

1

6 p

1

4 p

2

5 p

2

6 p

2

4 p

2

6 p

3

4 p

4

5 p

4

6 p

4

4 p

5

5 p

5

6 p

5

3 2

3 4

3 3

5 0

3 1

4 9

8 1

5 2

5 1

8 2

8 4

8 3

3 5

5 3

8 5

6 8

6 7

9 9

7 0

6 9

1 0 0

1 0 2

1 0 1

7 1

1 0 3

F m

N o

E r

E s

M d

H o

T m

Y b

T l

G a

I n

P b

G e

S n

B i

A s

S b

P o

S e

T e

L r

L u

A t

B r I

5 p

3

4 p

6

5 p

6

6 p

6

3 6

5 4

8 6 R

n K r

X e

f i l l i n g p s u b - s h e l l s

3

4

5

6

7

0

2 p

1

3 p

1

2 p

2

3 p

2

3 p

3

2 p

4

3 p

4

2 p

5

3 p

5

6

5 1 3

8

7

1 4

1 6

1 5

9 1 7

T l

B

S i

C

P N

S O

C l

F

2 p

3

1 s

2

2 p

6

3 p

6

2 1 0

1 8

A r

H e

N e

1 s

1

1

H

2 s

1

3 s

1

2 s

2

3 s

2

P e r i o d

1 2 3

f i l l i n g s s u b - s h e l l s

1

2

G r o u p

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Figure 15 Dividing up the Periodic Table.

s block

d block

p block

metals non-metalsf block

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Cl

–

ion

Na+ ion

‘Pool’ of delocalised

electrons

attraction

nucleus

+ +

–

–

shared electrons

Figure 9 In a hydrogen molecule, the atoms are

held together because their nuclei are both

attracted to the shared electrons.

Li1.0

Be1.6

B2.0

C2.6

N3.0

O3.4

F4.0

Na0.9

Mg1.3

K0.8

Ca1.0

Rb0.8

Sr 1.0

Al1.6

Si1.9

P2.2

S2.6

Cl3.2

Br 3.0

I2.7

H2.2

Li1.0

Period

symbol

electronegativity

KEY

Group

2

1

1 2 3 4 5 6 7

3

4

5

Figure 2 The sodium chloride lattice, built up

from oppositely charged sodium ions and

chloride ions.

Figure 15 A model of metallic bonding.

Figure 13 Pauling electronegativity values for

some main group elements in the Periodic Table.

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Figure 17 The relative sizes of atoms and ions.

Figure 18 Ions with higher charge densities

attract more water molecules

(ions are only shown in two dimensions).

Na+ ion(charge 1+, radius 0.098nm)

On average, eachNa+ ion is surrounded by

5 water molecules

Mg 2+ ion(charge 2+, radius 0.078nm)

On average, eachMg 2+ ion has 15

water molecules around it

+ 2+

Figure 19 Hydrated ions are much bigger than

isolated ions.

Li+

(g)

isolated Li+ ion(radius = 0.078nm)

Li+ (aq)

hydrated Li+ ion (radius = 1.00nm)

Na+ (g)

Na+ (aq)

isolated Na+ ion(radius = 0.098nm)

Figure 36 Two isomers of alanine.

H

C

HOOC NH2CH3

H

C

COOHH2NH3C

Figure 38 The CORN rule. Look down the

H—C bond from hydrogen towards the central

carbon atom.

COOH COOH

C

H

CORN

L isomer

H2N

R

C

H

CORN

D isomer NH2

R

hydrated Na+ ion (radius = 0.79nm)

Li Li+

Li atom

r atom = 0.152 nm

Li+ ion

r ion = 0.078 nm

Na Na+

Na atom

r atom = 0.186 nm

Na+ ion

r ion = 0.098 nm

Mg Mg2+

Mg atom

r atom = 0.160 nm

Mg2+ ion

r ion = 0.078 nm

F F –

F atom

r atom = 0.071 nm

F – ion

r ion = 0.133 nm

O O2 –

F atom

r atom = 0.073 nm

F – ion

r ion = 0.132 nm

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E n t h a l p y

reactants products

Progress of reaction

chemicalreactants

energy given outto surroundings∆H negative

eg CH4+2O2

products

eg CO2+2H2O

Figure 1 Enthalpy level diagram for an

exothermic reaction, eg burning methane:

CH4 +2O2 g CO

2 + 2H

2O.

thermometer

water

electrically heatedwire to ignite sample

air jacket

oxygen underpressure

crucible containingsample under test

stirrer

Figure 3 A bomb calorimeter for making

accurate measurements of energy changes. The

fuel is ignited electrically and burns in the

oxygen inside the pressurised vessel. Energy istransferred to the surrounding water, whose

temperature rise is measured.

Note that the experiment is done at constant

volume in a closed container. Enthalpy changes

are for reactions carried out at constant pressure ,

so the result needs to be modified accordingly.

energy taken infrom surroundings∆H positive

chemicalreactants

eg CaCO3

E n t h a l p y

reactants

products


products

eg CaO+CO2

Figure 2 Enthalpy level diagram for an

endothermic reaction, eg decomposing calcium

carbonate:

CaCO3 g CaO + CO

2.

∆H going this way...

... is the sameas ∆H going

this way

CH4(g)

CO2(g) + 2H2O(I)

C(s) + 2H2(g)

Figure 4 An enthalpy cycle for finding the enthalpy

change of formation of methane, CH 4.

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E n e

r g y

+

breaking bonds(takes in energy)

making new bonds(gives out energy)

H

H

O O

O O

C H

O O O O

H H H

C OOO

HH

O

HH

C

HH

Figure 9 Breaking and making bonds in the reaction between methane and oxygen.

Solid Liquid Gas

particles in fixed positions particles moving around

regular lattice pattern random arrangement

particles close together particles widely separated

volume depends only slightlyon pressure and temperature

volume depends strongly ontemperature and pressure

Figure 14 A comparison of solids, liquids and

gases.

Increasingenergy

each rotationallevel has its own

translational levels

each vibrationallevel has its own

rotational levels

each electroniclevel has its own

vibrational levels

groundelectronicenergylevel

vibrationalenergylevels

rotationalenergylevels

translationalenergylevels

Figure 15 Each electronic energy

level has within it several

vibrational, rotational and

translational energy levels. Note

that the levels are not to scale.

‘stack’ of ‘stack’ of ‘stack’ of

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ionic lattice + solvent solution

gaseous ions+

solvent

∆H solution

∆H LE ∆H hyd(cation)+

∆H hyd(anion)

Figure 21 An enthalpy cycle to show the

dissolving of an ionic solid.

Figure 26 Born–Haber cycle for sodium

chloride.

NaCI(s)Na(s) + ½CI2(g)

Na+(g) + CI-(g)Na(g) + CI(g)

∆H 2

∆H 1

∆H 3

∆H 4

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Figure 27 Born–Haber cycles for sodium chloride and potassium chloride.

Enthalpy/kJmol –1

Na+(g) + Cl(g)

+800

+700

+600

+500

+400

∆H i (1)(Na)

∆H EA(1)(Cl)

Na+(g) + Cl(g)

K+(g) + Cl(g)

∆H i (1)(K)

K+(g) + Cl(g)

K+(g) + Cl –(g)

∆H EA(1)(Cl)

+400

+200

+100

0

+300

–100

–200

–300

–400

–500

Na(g) + Cl(g)

∆H at (Cl)

Na+(g) + 12 Cl2(g)

∆H at (Na)

Na(s) + 12 Cl2(g)

∆H f (NaCl)

NaCl(s)

∆H LE(NaCl)

∆H at (Cl)

K(g) + 12 Cl2(g)

∆H at (K)

K(s) + 12 Cl2(g)

∆H f (KCl) ∆H LE(KCl)

KCl(s)

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Figure 27 Born–Haber cycles for sodium chloride and potassium chloride.

Enthalpy/kJmol –1

Na+(g) + Cl(g)

+800

+700

+600

+500

+400

Na+(g) + Cl(g)

K+(g) + Cl(g)

K+(g) + Cl(g)

K+(g) + Cl –(g)

+400

+200

+100

0

+300

–100

–200

–300

–400

–500

Na(g) + Cl(g)

Na+(g) + 12 Cl2(g)

Na(s) + 12 Cl2(g)

NaCl(s)

K(g) + 12 Cl2(g)

K(s) + 12 Cl2(g)

KCl(s)

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Figure 2 What happens when an ionic substance

such as sodium chloride dissolves in water.

Figure 5 Polar water molecules attract the ions in

a solid lattice.

Figure 11 (a) The structure of diamond and (b)

the structure of graphite.

(a) (b)

Figure 12 Imagine you are inside a diamond. The

regular network structure would repeat in all

directions – as far as the edge of the diamond.

Figure 13 The fullerenes are a recently discovered

molecular form of carbon.

(a) shows C 60 , named buckminsterfullerene.

It is made up of a mixture of 5-membered and 6-

membered rings and looks like a football

(b) is another way of presenting C 60 , showing the

positions of the carbon atoms

(c) shows C 70 , which is shaped like a rugby ball.

(a) (b) (c)

– + –

– –

– –

– –

– –

–

–

+

+ +

+ +

+ +

+

+

+

+

Solid sodium chloridea retular ionic lattice

Cl – Na+ Cl –(aq) Na+(aq) water molecule

Sodium chloridedissolved in water

δ−δ+

solid lattice

polar water molecule

hydrated ions

+

–

+

+

+ +

+ +

+ + +

+ + +

–

– –

– –

– –

– – –

δ−

δ−

δ−

δ−

δ−

δ−

δ−

δ−

δ−

δ−

δ−δ−

δ−

δ−δ+

δ+

δ+

δ+

δ+ δ+

δ+

δ+

δ+

δ+

δ+

δ+

δ+

δ+

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Figure 14 On heating, the molecular substance

(represented by ) changes from a solid to a

liquid and then to a gas. Energy must be supplied

to overcome the intermolecular forces. Note that the covalent bonds within the molecules remain

intact.

heat

m.p.

heat

b.p.

Solid Liquid Gas

δ + δ –

At some instant, more of the electroncloud happens to be at one end of themolecule than the other; moleculehas an instantaneous dipole.

Electron cloud evenlydistributed; no dipole.

Cl Cl Cl Cl

Figure 15 How a dipole forms in a chlorine

molecule.

This atom is not yetpolarised, but itselectrons are repelledby the dipole next to it ...

Xe

This atom isinstantaneouslypolarised

Xeδ + δ – Xeδ + δ –

... so it becomespolarised

Xeδ + δ –

Figure 18 How an induced dipole is formed in a

Xe atom.

B o i l i n g p o i n t / K

400

300

200

100

Period2 3 4 5

H2TeSbH3HISnH4

H2O

HF

NH3

CH4

Group 4Group 5Group 6Group 7

Figure 20 Variation in the boiling points of the

hydrides of some Group 4, 5, 6 and 7 elements.

E n

t h a l p y c h a n g e o f

v a p

o r i s a t i o n / k J m o l - 1

l

40

20

0

Period2 3 4 5

H2TeSbH3HISnH4

H2O

HF

NH3

CH4

Group 4Group 5Group 6Group 7

Figure 21 Variation in the enthalpy changes of

vaporisation of some Group 4, 5, 6 and 7

elements.

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Lone pair;concentratednegative

charge

F

H

H

δ +

Fδ–

Figure 23 The positively charged H atom lines

up with the lone pair on an F atom.

H

HHH

O

Hydrogen bond

Lone pair

O

HH

O

Figure 25 The positively charged H atoms line

up with the lone pairs on the O atoms.

Key

oxygen

hydrogenhydrogen bond

Figure 28 The arrangement of water molecules

in ice.

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HEAT

easily broken by heating; polymer canbe moulded into new shape.

chains cannot be easily broken; polymer keeps shape on heating.

polymer chain

cross–link

Figure 29 Thermoplastics and thermosets.

crystalline region

amorphous region

Figure 32 Crystalline and amorphous regions of

a polymer.

GIANTLATTICEgoes on

indefinitely

STRUCTURES

MOLECULARmade of groups of atoms

COVALENTMOLECULAR

COVALENTNETWORK

METALLICIONIC MACROMOLECULAR(eg polymers)

Figure 36 A summary of the structures of

substances.

(a) Thermoplastic: no cross–linking

HEAT

Weak forces between polymer chains

(b) Thermoset: extensive cross–linking Strong covalent bonds between polymer

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Figure 3 Obtaining a line emission spectrum.

Figure 4 Obtaining a line absorption

spectrum.

electron hasbeen excitedto level 5,drops back tolevel 1

etclevel 5level 4

level 3

level 2

level 1

groundstate

Lyman series

this line

correspondsto electronsdroppingfrom level 5 1

1 2

1 3

1 5

2 1 3 1 4 1

1 4

Frequency

Figure 6 How the Lyman series in the

emission spectrum is related to energy

levels in the H atom.

wire with sampleof element

excited atoms

in hot flameemit light

slit

prism

line emission spectrum(bright lines on a blackbackground)

source of white light

wire with sampleof element

cool flame:most atoms invapour are in their ground state line absorption spectrum (black lines

on a bright coloured background)

slit

prism

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Increasingenergy

Cl

H

ELECTRONICENERGY

VIBRATIONALENERGY

ROTATIONALENERGY

TRANSLATIONALENERGY

Cl H

Cl H

Cl

H

Cl H Figure 7 An HCl molecule has energy associated

with different aspects of its behaviour.

Figure 16 The basic parts of a double beaminfrared spectrometer.

3000 2000 1000

Wavenumber/cm –1

T r a n s m i t t a n c e / %

100

80

60

40

20

Figure 21 Infrared spectrum of butane.

Absorption/cm –1 Bond2970 C—H (alkane)

CH3 CH2 CH2 CH3

sample cell for solution of sample

infrared source(electrically heatedfilament)

reference cellfor solvent only

NaCl prism(or diffraction

grating)

infrareddetector

chart recorder

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3000 2000 1000

Wavenumber/cm –1


100

80

60

40

20

Figure 23 Infrared spectrum of benzoic acid.

Absorption/cm

–1

Bond3580 O−H3080 C−H (arene)1760 C=O

COHO

Figure 22 Infrared spectrum of methylbenzene.

Absorption/cm –1 Bond3050 C−H (arene)2940 C−H (alkane)

CH3

powerfulmagnet

sample

RF signalgenerator

detector

recorder

SN

Figure 37 A simplified diagram of an n.m.r.

spectrometer.

N S

N S

E2

E1

∆Ealigned against

magnetic field

aligned withmagnetic field

N S

NS

Figure 36 The principle of n.m.r.: a small

magnet in a strong magnetic field can have two

different energies.

100

80

60

40

20

3000 2000 1000

Wavenumber/cm –1


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Chemical Relative Type of shift no. protons proton0.9 3 CH31.3 4 CH2

CH3 CH2 CH2 CH2 CH2 CH3

A b s o r p t i o n

012345

Chemical shift

8H

6H

TMS

678910

Figure 43 N.m.r. spectrum of hexane.

Chemical Relative Type of shift no. protons proton1.6 3 CH3

5.6 1

C C

H

CH3

H3C

H

H C C H

Figure 44 N.m.r. spectrum of trans-but-2-ene.

A b s o r p t i o n

012345

Chemical shift

3H

2H

2H

1H

TMS

678910

Chemical Relative Type of shift no. protons proton0.9 3 CH3

1.6 2

2.3 1 OH

3.6 2

CH3

CH2

CH2

OH

C CH2 C

C CH2 O Figure 45 N.m.r. spectrum of propan-1-ol.

transparent object,glass or a solution

all wavelengths of visible light transmitted:appears colourless

all wavelengthsof visible lightreflected:appears white

opaque object,eg a piece of chalk

Figure 52 How light behaves with transparent

and opaque objects.

Chemical shift

A b s o

r p t i o n

6H

TMS2H

10 9 8 7 6 5 4 3 2 1 0

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transparent object

absorbsred

transmits wavelengths correspondingto other colours: appears green

reflects wavelengths corresponding toother colours: appears orange

opaqueobject absorbs blue

Figure 53 How colours arise from absorption of

light.

I

n t e n s i t y o f a b s o r p t i o n

ultra violet

visible

infra red

260

300

340

380

420

460

500

540

580

620

660

700

Wavelength/nm

ultra violet visible

violet blue green yellow red

infra red

Figure 57 The absorption spectrum of carotene

(in solution in hexane).

λ /nm

blue light istransmitted

blue light isreflected(Reflectancespectrumshown below)

opaque,colouredobject,eg painting

I n t e n s i t y o f a b s o r p t i o n

absorption spectrum

R e f l e c t a n c e

reflectance spectrum

red and yellow lightis absorbed. (Absorptionspectrum shown below)

transparentcolouredobject, egsolution

600 700500400 600 700500400

paint layer absorbsred and yellowlight

100

0

λ /nm

Figure 59 Absorption and reflectance spectra of

Monastral Blue.

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excitationenergy excited electronic state

energy absorbed corresponds toultraviolet light

excitation energies inthis region correspond to visible radiation

energy absorbed corresponds tovisible light

excited electronic state

ground electronic states

COLOUREDCOMPOUND

COLOURLESSCOMPOUND

Figure 63 The energy needed to excite an

electron in a coloured compound and in a

colourless compound.

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Figure 5 The pH scale.

H+ (aq) +

stays roughlyconstantbecause

plenty of HA to make moreH+ (aq) if some used up by alkali that gets added

plenty of A – to combine

with any H+(aq) that getsadded

A –HA

Figure 6 How a buffer solution keeps the pH

constant.

pH [H+(aq)]/mol dm –3

Moreacidic

Neutral

Morealkaline

0

1

2

3

4

5

6

7

8

9

10

11

12

13

1

10 –1

10 –2

10

–3

10 –4

10 –5

10 –6

10 –7

10 –8

10 –9

10 –10

10 –11

10 –12

10 –13

14 10 –14

–

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Figure 2 The reaction of chlorine with potassium

iodide solution.

+

–

–

Cu2+ ion+

–

–

–

+

–

+

+

+

+

SO42– ion

–

Zn atom

Cu atom

– –

–

– –

–

+

+

+ +

+

SO42– ion –

+

Zn2+ ion+

Figure 4 The reaction of zinc with

copper(II) sulphate solution:

Zn(s) + Cu2+

(aq) g Cu(s) + Zn2+

(aq)

Figure 5 The general arrangement for an

electrochemical cell.

Velectronflow

ELECTRONSRELEASED

ELECTRONS ACCEPTED

oxidationreaction

reductionreaction

Figure 6 An ordinary dry cell – the kind you use

in a torch.

– + I – ion

I2 molecules

Cl – ion

K+ ionK+ ion

Cl2

molecules

–

– –

– –

–

– –

– –

– –

–

++

+

+ ++

++ +

++

+

+

seal+

electronflow alongexternalwire

mixture of chemicalscontaining ammoniumchloride which acceptselectrons and isreduced

card covering

zinc container (–) terminalzinc supplies

electrons and isoxidised

carbon rod(+) terminal

–

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27/47

platinum electrode

solution containing

equal concentrationsof Fe2+(aq) andFe3+ (aq)

Figure 12 A standard half-cell for the

Fe3+

(aq)/Fe2+

(aq) half-reaction.

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Figure 2 Enthalpy profile for an exothermic

reaction.

N u m b

e r o f m o l e c u l e s w i t h

k i n e t i c e n e r g y E

Kinetic energy (E )

300 K

310 K

Figure 4 Distribution curves for molecular

kinetic energies in a gas at 300 K and 310 K.

Figure 5 Distribution curve showing collisions

with energy 50 kJ mol –1

and above.

Figure 6 Distribution curves showing the effect

on the proportion of collisions with energy

50 kJ mol –1 and above of changing the

temperature from 300 K to 310 K.

X

Activation enthalpy

Reactants∆H

Products


E n t h a l p y

Activation enthalpyE a= 50 kJ mol

–1

Kinetic energy (E )

N u m b e r o f c o l l i s i o n s w i t h


300 K

310 K

Number of collisions withenergy greater than50 kJ mol –1 at 310 K

Number of collisions withenergy greater than50kJ mol–1 at 300 K

Kinetic energy (E )

Activation enthalpyE a= 50 kJ mol

–1

N u m

b e r o f c o l l i s i o n s w i t h


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invertedburette

water

yeastsuspension+ hydrogen

peroxidesolution

Figure 8 Apparatus for investigating the rate of

decomposition of hydrogen peroxide. The yeast

provides the enzyme catalase.

Figure 10 The decomposition of hydrogen

peroxide solutions of differing concentrations.

Figure 11 The initial rate of decomposition of

hydrogen peroxide plotted against concentration

of hydrogen peroxide.

[H2O2] =0.40 mol dm –3

[H2O2] =0.40 mol dm –3

[H2O2] =0.40 mol dm –3

[H2O2] =0.40 mol dm –3

[H2O2] =0.40 mol dm –3

V o l u m e O 2 / c m

3

Time /s

262422

201816

14121086

42

0 20 40 60 80 100 120 140 160 180

R a t e o

f r e a c t i o n / c m

3 ( O 2 ) s – 1

0.5

0.4

0.3

0.2

0.1

0 0.1 0.2 0.3 0.4

Concentration of hydrogenperoxide/mol dm –3

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Second bondforms, and productdiffuses away fromcatalyst surface,leaving it free toadsorb freshreactants.

4

H H H

C

H C

H

H

H

H

New bond forms.

H

C

H C

H

3

HH H

H

H

C

H

C

H

H

H

HH HH

Bonds break.2

Reactants get

adsorbed ontocatalyst surface.Bonds are weakened.

1

HH CH

C

H

H

H

HH

catalyst surface

H H

C

H

C H

H

H

C H C

H

H

H

H H

Figure 18 An example of heterogeneous

catalysis. The diagrams show a possible

mechanism for nickel catalysing the reaction

between ethene and hydrogen to form ethane.

activation enthalpyuncatalysed reaction

activation enthalpycatalysed reaction

uncatalysedreaction

catalysedreaction

reactants

products

∆H

E n t h a l p y


Figure 19 The effect of a catalyst on the enthalpy

profile for a reaction.

E n t h a l p y


Figure 19 The effect of a catalyst on the enthalpy

profile for a reaction.

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D e n s i t y / g c m – 3

2

1

3

0Li Be B C N O F Ne Na Mg Al Si P S Cl Ar

Figure 3 Densities of elements in Periods

2 and 3.

Figure 4 Melting and boiling points of elements

in Period 3.

M e l t i n g a n d b o i l i n g

p o i n t s /

K

Na Mg Al Si P S Cl Ar

m.p.

Key

b.p.

1000

0

2000

3000

Figure 5 Variation in atomic size across Period 3.

A t o m i c r a d i u s

/ n m

Na Mg Al Si P S Cl Ar

0.2

0.1

0

F i r s t i o n i s a t i o n e n t h a l p y / k J m o I – 1

1000

0H He Li Be B C N O F Ne NaMg Al Si P S Cl Ar K Ca

2000

Figure 6 First ionisation enthalpies of elements

1–20.

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Element Atomic number Electronic arrangement

3d

Sc

Ti

V

Cr

Mn

Fe

Co

Ni

Cu

Zn

21

22

23

24

25

26

27

28

29

30

[Ar]

[Ar]

[Ar]

[Ar]

[Ar]

[Ar]

[Ar]

[Ar]

[Ar]

[Ar]

building up of inner3d sub-shell

outer shell

4s

Figure 20 Arrangement of electrons in the

ground state of elements of the first row of the d

block. [Ar] represents the electronic

configuration of argon.

force

(a) (b)

force The open circles representatoms of iron. The blackcircles are the larger atomsof a metal added to make analloy.

Figure 22 The arrangement of metal

atoms in a crystal (a) before and (b) after

slip has taken place. The shaded circles

represent the end row of atoms.

Figure 23 The arrangement of metal

atoms in an alloy.

Sc Ti V Cr Mn Fe Co Ni Cu Zn

+1

+5

+7

+4 +4 +4

+2 only+2+2 +2 +2 +2 +2 +2

+6 +6 +6

+3 only +3 +3 +3 +3 +3 +3 +3 +3

Figure 24 Oxidation states shown by elements inthe first row of the d block. The most important

oxidation states are in boxes.

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Figure 27 An octahedral complex of Fe(III). Coordination number 6.

Figure 28 A tetrahedral complex of Ni(II). Coordination number 4.

Figure 29 A square planar complex of Ni(II). Coordination number 4.

Figure 30 A linear complex of Ag(I).

Coordination number 2.

Figure 32

(a) Edta4– , a hexadentate ligand.

(b) The nickel–edta complex ion [Ni(edta)]2 –

.

octahedral complex of FE(III)coordination number 6

CN

CN

CN

CN

NC

NC

Fe

3–

shape

CN

NC

Fe

NC

NC

NC

Fe

CN

CN

CN

CN

CN

CN

CN

ClCl

ClCl

Cl Cl

ClCl

Cl Cl Cl

Cl

NiNiNi

tetrahedral complex of Ni(II)

coordination number 5shape

2–

Ni Ni Ni

NC

NC

NC

NC NC

NC

CN

CN

CN

CN

CN

CN

2–

square planar complex of Ni(II)

coordination number 4

shape

H3N Ag NH3+

O

CO

O O

O

OO

O

O

O

O

O

O

O

O

C

C

CH2

C

C

C

C

C

CH2 CH2

CH2

CH2

CH2

CH2 CH2

CH2

CH2

H2C

H2C

2–

Ni

(a)

(b)

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Figure 33 Relative energy levels for the five 3d

orbitals of the hydrated Ti 3+ ion.

Figure 36 The cis and trans isomers of

[Co(NH 3 )

4Cl

2 ]+ have different colours.

energy

Average energy

of 3d orbitals in[Ti(H2O)6]

3+

if there was no

splitting [Ti(H2O)6]3+

ground state

3d level split

[Ti(H2O)6]3+

excited state

light

hv ∆E

cis isomer: violet trans isomer: green

NH3

NH3

NH3

H3N

NH3 NH3

NH3

NH3

Cl

Cl

Cl

Cl

Co Co

++

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Name Molecular Full structural Shortened Further formula formula structural shortened

formula to

methane

ethane

propane

Table 2 Structural formulae of alkanes.

CH4CH4 H C H

H

H

C2H6 H C C

H

H

H

H

H

CH3CH3CH3 CH3

C3H8 H C C C

H

H H H

H H

H CH3CH2CH3CH3 CH2 CH3

109°

represents a bond inthe plane of the paper

represents a bond ina direction behindthe plane of the paper

represents a bond ina direction in front ofthe plane of the paper

H

C

H H

H Figure 5 The three-dimensional shape of

methane.

a simpler way of drawingethane which shows theshape less accurately

C C

H

H

H

H

H

H

Figure 6 The three-dimensional shape of ethane.

C C

H

HH

HH

H

Figure 7 The three-dimensional shape of butane.

C

C

C

C

H

HH

HH

H

H

H

H

H

skeletal formulaof butane

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A L K A N E S

I s o m e r i s a t i o n

R e f o r m i n g

C r a c k i n g

S t e a m c r a c k i n g

C a t a l y t i c c r a c k i n g

F e e d s t o c k

C

4 – C 6 a l k a n e s

n a p

h t h a

n a p h t h a / k e r o s e n e

g a s o i l

P r o d u c t

s a m e m o l e c u l a r f o r m u l a a s

s a m

e n u m b e r o f C

a t o m s a s r e a c t a n t s ;

m o r e m o l e c u l e s ;

m o r e m

o l e c u l e s ;

m o l e c u l e s

r e a c t a n t s ;

c y c

l i c

f e w e r C

a t o m s t h a n r e a c t a n t s ;

f e w e r C

a t o m s t h a n r e a c t a n t s ;

b r a n c h e d

s m a l l m o l e c u l e s , s u c h a s

s o m e u

n s a t u r a t e d ;

C 2 H 4 ,

C 2 H 6 ,

C 3 H 6 ,

C 3 H 8 ,

s o m e b

r a n c h e d ;

C 4 a n d C 5 a l k e n e s a n d

s o m e c

y c l i c

a l k a n e s

C o n d i t i o n s

P

t / A l 2 O 3 ;

P t / A

l 2 O 3 ;

n o c a t a l y s t ;

z e o l i t e ;

1 5 0 ° C

5 0 0

° C ;

9 0 0 ° C ;

5 0 0 ° C

h y d

r o g e n i s r e c y c l e d t h r o u g h m i x t u r e t o

s h o r t r e s i d e n c e t i m e ;

r e d u c e ‘ c o k i n g ’

s t e a m i

s a d i l u t e n t t o p r e v e n t

‘ c o k i n g ’

E x a m p l e

U s e s o f

t o

i m p r o v e o c t a n e r a t i n g o f p e t r o l

t o i m p r o v e o c t a n e r a t i n g o f p e t r o l

t o m a n u f a c t u r e p o l y m e r s

t o i m p r

o v e o c t a n e r a t i n g o f p e t r o l

p r o d u c t s

F u r t h e r

D

e v e l o p i n g F u e l l s s t o r y l i n e ,

D e v e l o p i n g F u e l s s t o r y l i n e ,

T h e P o l y m e r R e v o l u t i o n

D e v e l o

p i n g F u e l l s s t o r y l i n e ,

d e t a i l s

S e c t i o n D F 4

S

e c t i o n D F 4

s t o r y l i n e ,

S e c t i o n s P R 3

S e c

t i o n D F 4

C h e m i c a l I d e a s 1 5 . 2

a n d P R 4

C h e m i

c a l I d e a s 1 5 . 2

C h e m i c a l I d e a s 1 5 . 2

T a b l e 5

T h e a c t i o

n o f h e a t o n a l k a n e s . S k e l e t a l f o r m u l a e a r e

u s e d i n t h e e x a m p l e s .

i s t h e s k

e l e t a l f o r m u l a f o r a b e n z e n e r i n g .

+

+

+

H 2

+

3 H 2

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C–C bond length0.139 nm

120°

C

CC

C

CCH

H

H

H

H

H

Figure 11 The structure of the benzene ring.

Scale 0.1nm0

Figure 14 An electron density map for benzene

at –3 °C. The lines are like contour lines on a

map: they show parts of the molecule with equal

electron density.

Figure 15 Enthalpy changes for the

hydrogenation of benzene and the hypothetical

Kekulé structure.

regions of higher electrondensity above and belowthe benzene ring

Figure 16 The regions of higher electron density

above and below the benzene ring.

E n t h a l p y


∆H = –360 kJ mol –1

(estimated enthalpy change

for Kekulé’s benzane)

C6H12 cyclohexane

+ 3H2

+ 3H2

∆H = –208 kJ mol –1

measured enthalpy

change for benzane)

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Full structural Skeletal Nameformula formula

1-chloropropane

1,2-dichloropropane

3-bromo-1-chlorobutane

Table 1 Naming halogenoalkanes.

Cl

H

C

H

H C C

H

H

Cl

H

H

Cl

ClH

C

H

H C C

Cl

H

Cl

H

H

Cl

BrH

C

H

H C C

Br

H

C

H

H

Cl

H

H

Table 3 Some common nucleophiles.

Full structural Skeletal Nameformula formula

propan-1-ol

propan-2-ol

pentan-3-ol

Table 4 Naming alcohols.

H

C

H

H C C OH

H

H

H

H

OH

H

C

H

H C C H

OH

H

H

H

OH

H

C

H

H C C C

H

H

OH

H

C H

H

H H

H

OH

Name and Structure, showingformula lone pairs

hydroxide ion,OH –

cyanide ion,CN –

ethanoate ion,CH3COO

–

ethoxide ion,C2H5O

–

water molecule,H

2O

ammoniamolecule,NH3

H

H H

H HH

O

O

O

O

O

N

CH3

CH3CH2

N C

C

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Table 6 Some examples of acid derivatives.

Acid derivative Dealt with in Section(s) Example

13.5 and 14.2

13.5 and 14.2

13.8

13.5 and 14.2

ester

acyl chloride

amide

acid anhydride

C

O

OR

C

O

Cl

C

O

NH2

C

O

O

C

O

ethyl ethanoate

ethanoyl chloride

ethanamide

ethanoic anhydride

CH3 C

O

O

CH3 C

O

Cl

CH3 C

O

NH2

CH3 C

O

O

CCH3

O

CH2CH3

Type of alcohol Position of —OH Examplegroup

primary at end of chain: propan-1-ol

secondary in middle of chain: propan-2-ol

tertiary attached to a carbonatom which carriesno H atoms: 2-methylpropan-2-ol

CH3CH2 C OH

H

H

CH3 C CH3

H

OH

CH3 C CH3

CH3

OH

Table 7 Primary, secondary and tertiary alcohols.

H

C

H

R OH

H

C

OH

R R'

R'

C

OH

R R''

Figure 6 How to name an ester.

ethyl ethanoate

This part comes from

the alcohol and is

named after it

This part comes

from the acid and

is named after it

O

OCH3

CH3

CH2

C

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H

CH O C

C

O

H

C

O

H

H

O

C

C

O

O

R1 (long carbon chain)

R2

R3

glycerol part −

always the same

fatty acid parts − R1, R2 and R3

may be different or the same

Figure 7 The general structure of the triesters

found in fats and oils.

O

O

O

O

O

Unsaturated triglyceride

O

O

O

O

O

O

O

Saturated triglyceride

Figure 9 Representations of triglycerides.

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carboxylic acid amine amide group

C

O

N C

O

H

+ H2ON

O

H

H

H

Figure 18 Making a secondary amide.

acid groupamino group

α-carbon: the first carbon atomattached to the –COOH group

H

R

H2N C COOH

Figure 20 The generalised structure of an α-amino acid.

Figure 21 How an amino acid forms a zwitterion.

C

R

H

C

O

OH

N

H

H

C

R

H

C

O

O−

N

H

H

H

receives H+ froma COOH group

H+ donated toan NH2 group

a zwitterion

+

+

azo compound

N + H+N

diazonium ion

NN+

coupling agent

H

Figure 22 A generalised coupling reaction.

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+ HCl(g)sunlight

Cl2(g)

room temp alkene

naddition polymer

trace O2(g)

200 oC and

1500 atm.

H2O(g)

phosphoric

acid catalyst

300 oC and 60 atm.

HBr

conc H2SO4followedby H2O

or

organic solvent

Br2

organic solvent

H2(g)

finely divided Ni

at 150 oC and 5 atm.

(or Pt at room tempand 1 atm.)

HC CH

CH2 CH2

HC CH

H Br

HC CHHC CH

H OH

HC CH

Br Br

CH2 CH

Cl

Figure 2 Reactions of alkenes.

Figure 3 Reactions of halogenoalkanes.

alcohol

heat in asealed tube

halogenoalkane

c. NH3(aq)

H2O(l)

NaOH(aq)

amine

alcohol

slow

reflux

R OH

R HalR NH2

R OH

R CH2 O C R'

O

R CH2 OH

R CHO R COOH

R CH2 Br

R CH2 Cl

R CH CH2

ester

bromoalkane

chloroalkane

carboxylic acid aldehyde

alkene primary alcohol

R'−COCl

or (R'CO)2O

anhydrous

conditions

R'−COOH

c. H2SO4 catalyst

reflux

c. HCl

HBr(aq)

(NaBr(s) + c. H2SO4)

reflux

Cr2O72− /H+(aq)

reflux

Cr2O72− /H+(aq)

reflux

NaBH4

Al2O3(s), 300 °C

or c. H2SO4reflux

Figure 4 Reactions of primary alcohols.

room temp

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R

O

C

H

carboxylate ion

carboxylic acid

NaOH(aq) HCl(aq)

R'

O –

O

R

O

C

OHc. H2SO4 catalyst

reflux with

aqueous acid or alkali*

R

O

C

O

R C

O

acid anhydride

R' OH

anhydrous

conditions

reflux

R

O

C

O R'

ester

R' OHroom

temperature

acyl chloride

R

O

C

Cl

R' NH2

room

temperature

room

temperature

primary amide

R

O

C

NH2

c. NH3(aq)

RO

C

NH R'

secondary amide

R C

O

H

aldehyde

C

OH

H

CN

RC

OH

H

H

R

primary alcohol a cyanohydrin

R C

O

OH

carboxylic acid

HCN

(+ alkali)

NaBH4

Cr2O72− /H+(aq)

reflux

or heat with

Fehling's

solution

R C

O

R'

ketone

C

OH

R'

CN

RC

OH

R'

H

R

secondary alcohol a cyanohydrin

HCN

(+ alkali)

NaBH4

Figure 6 Reactions of ketones.

Figure 5 Reactions of aldehydes.

Figure 7 The reactions of carboxylic acids and some related compounds.

Note Esters and amides are both hydrolysed by heating with aqueous acid or aqueousalkali. Alkaline hydrolysis gives the salt of the corresponding carboxylic acid. The freecarboxylic acid is formed on acidification of the solution.

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Figure 8 Reactions of arenes.

Cl

Cl2(g) AlCl3

room

temperature

NO2c. HNO3

c. H2SO4

< 55 °C

alkylation

R

R Cl AICI3

reflux

Friedel-Crafts

reactions

R COCl or (RCO)2O

acylation

O

CR

finely divided Ni

H2(g)

300 °C, 30 atm.

Br 2(l)FeBr 3 (or FE)

room

temperature

Br

SO2OH

c. H2SO4reflux

AICI3reflux

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Feedstock(reactants)

Feedstockpreparation

Energy in or out

REACTION

Temperature, pressure, catalyst

Separation

Products

Co-products

Recycle loop Unused feedstock

Input or removal of energy may be required at any stage

(and by-products)

Figure 1 Sequence of unit operations in a

chemical plant.

Startingmixture

Batch reactor At start Reactants in Some time later

Productmixture

Continuous (stirred tank) reactor

Stirrer

Product mixturecontinuously removed

Reactants added continuously

(a) (b)

Figure 2 Comparison of (a) batch and

(b) continuous tank reactors.

LiverpoolManchester

Castner/Kellner

Works

Lancaster

Durham

Newcastle

SunderlandCarlisle

Annan

Dumfries

Selkirk

Jedburgh

Peebles

Lanark

Stirling

Kelso

Hawick

Glasgow

Edinburgh

STRATHCLYDE

DUMFRIES &

GALLOWAY

Kendal

Chester

Hillhouse Works

CLWYD CHESHIRE

LANCASHIRE

CUMBRIA

NORTH WESTERN

ETHENE PIPELINE

SOLWAY FIRTH

WILTON

GRANGEMOUTH

TRANS PENNINE

ETHENE PIPELINE

NORTH

YORKSHIRE

NORTHUMBERLAND

FIRTH OF FORTH

ETHENE

PIPELINE

Wilton Works

MOSSMORRAN

GRANGEMOUTH

Figure 3 Pipelines from BP, Grangemouth, and Exxon, Mossmorran, for the distribution of

ethene.

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OIL

Fractionaldistillation

LPG Naphtha

Steamcracking

Ethene,propene

Steamcracking

Ethene,propene

Reforming

Branched alkanes, cycloalkanesand aromatic hydrocarbons

for high-grade petrol

Catalyticcracking

Gas Oil

Ethene, propene,high-grade petrol

ResidueKerosene

Figure 5 Feedstocks from oil.

Figure 4 Feedstocks from natural gas.

NATURAL GAS

Fractionaldistillation

Steamcracking

Methane Ethane

Ethene,propene

Steamcracking

Propane

Ethene,propene

Steamcracking

Butane

Ethene,propene

Figure 6 (a) An example of how energy can be used in a chemical process. (b) A diagram to illustrate a heat exchanger.

(a)

Reactants

at 20°C

(a)Heat exchanger

Reactants

at 20°C

Reactants

at 180°C

Reactor

at 200°C

Products at 200°C

Products at about 60°C

(b) Steamin Steamout Hotfeed out

Cold

feed in

Cross section:Condensed

steamSteam pipe

A single-pass tubular heat exchanger

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