C hem F actsheet Number 83
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The Chemistry of Copper To succeed in this topic you need to understand: the basic basicss of trans transiti ition on metals metals (cove (covered red in Facts Factsheet heet 28); 28); • the reacti reactions ons of tran transit sition ion metal metal ions ions with hydro hydroxide xidess and ammoni ammoniaa (covered (cover ed in Factsh Factsheet eet 46); • the princip principles les of oxidati oxidation on and and reductio reduction n (covered (covered in Factshee Factsheett 11). 11).
Oxidation states The oxidation states of copper are +1 and +2.
Principal compounds and ions are as follows. • CuI The copper(I) ion, Cu+, copper(I) oxide, Cu2O, copper(I) chloride, CuCl, and various complex ions such such as [CuCl2] . There is no hydroxide.
After working through this Factsheet you will: • know that that copper copper will will not not liberat liberatee hydrogen hydrogen from from dilut dilutee acids acids but is attacked by oxidising acids; acids; • know tha thatt the oxida oxidatio tion n states states of of copper copper are are +1 and +2; +2; • unde underst rstand and the the actio action n of water water on coppe copper(I r(I)) salts salts;; • under understan stand d the relati relationsh onships ips between between the the principa principall compounds compounds of copper; copper; • unders understand tand the chemist chemistry ry of of both both copper(I copper(I)) oxide oxide and and copper(I copper(II) I) oxide; oxide; 2+ • und under erst stand and the the aque aqueou ouss chemi chemist stry ry of of Cu (aq); • know the the preparat preparation ion of of copper(I copper(I)) chloride chloride and its its reactio reaction n with with concentrated hydrochloric acid.
−
The element Copper (atomic number = 29) is the last member of the first series of d-block transition elements.(Remember that zinc is not a transition element.) Its electronic configuration is 1s2, 2s 2, 2p 6, 3s2, 3p 6, 3d10, 4s 1. This arrangement, in which all five 3d orbitals are fully occupied, is more stable than the alternative [Ar] 3d9, 4s2.
•
The elect The electro roni nicc confi configur gurati ation on of of the the Cu+ ion is 1s2, 2s2, 2p6, 3s2, 3p6, 3d10.
•
CuII Copper(II) oxide, CuO, copper(II) hydroxide, Cu(OH) 2, the copper(II) ion, Cu2+, and various complex ions such as the hydrated copper(II) ion, [Cu(H2O)6]2+.
•
The electr The electroni onicc confi configu gura rati tion on of the the Cu Cu2+ ion is 1s2, 2s2, 2p6, 3s2, 3p6, 3d9.
Stability of oxidation states Although CuI and Cu II are of comparable stability, the Cu + io ion n disproportionates in aqueous solution.
Copper is a brownish red metal with a high density (8.92 g cm 3). It has a high thermal conductivity (hence its use in saucepans) and a high electrical conductivity (hence its use in electrical wiring). −
Cu2+(aq) I O N T D A X I D Cu+(aq) WATER O R E D U C T I O N Cu(s)
Exam Hint - Do not say that copper is used for electricity cables, because this implies implies that it is used for overhead power lines. It is too heavy and expensive expensive for this purpose. purpose. Aluminium is used used instead.
Copper(I) sulphate, for example, an off-white solid, dissolves in water to give a blue solution of copper(II) sulphate and a reddish brown precipitate of copper.
Copper is a relatively unreactive metal but is attacked by oxidising acids, notably nitric acid and concentrated sulphuric acid.
Exam Hint - Disproportionation should be defined as the simultaneous oxidation and reduction of a single species or a single substance.
Practical 1 - The action of nitric acid on copper Heat a piece of copper foil in a boiling tube with dilute nitric acid. The copper dissolves to give a blue solution of copper(II) nitrate and brown fumes of nitrogen dioxide. Caution! These fumes are toxic. Copper atoms are oxidised to Cu2+ ions: at the same time, NO3- ions are reduced to molecules of NO which, with O2 from the air, become oxidised to molecules of NO2.
The copper(I) state is particularly stable in three circumstances. • At high high tempe temperat rature ures. s. Som Somee copper copper(II (II)) compou compounds nds decom decompos posee on heating into the corresponding copper(I) compounds, e.g. 2CuCl2(s) • •
Practical 2 - The action of hydrochloric acid on copper Heat a piece of copper foil in a boiling tube with dilute hydrochloric acid. Notice that there is no apparent reaction.
→
2CuCl(s) + Cl 2(g)
In in inso solu lubl blee comp compou ound nds, s, e.g e.g.. Cu Cu2O and CuCl. In com compl plex ex ion ions, s, e. e.g. g. [Cu [CuCl Cl2]- and [Cu(NH3)2]+.
Redox chart On the redox chart of copper (p 2), the principal compounds and ions have been arranged in order of oxidation number.
Copper lies below hydrogen in the electrochemical series and will not liberate hydrogen from dilute acid s.
• • •
1
Any moveme movement nt up the the chart chart repre represen sents ts an oxidat oxidation ion proce process, ss, for for which an oxidising agent is required. Movement Movem ent down down the the chart chart corre correspond spondss to reduc reduction tion.. For this this,, a reducing agent is needed. Movementt across Movemen across the chart chart is neither neither oxidati oxidation on nor nor reductio reduction, n, and and is achieved with reagents such as dilute acids, NaOH(aq), NH3(aq) or Na2CO 3(aq).
t e e h s t c a F m e h C
OUTLINE CHEMISTRY OF COPPER
OXIDATION NO. OF Cu
Heat Conc. HCl
[CuCl4]2
CuO
+2
−
Black Solid Insoluble, Basic
[Cu(H2O)6]2
NaOH(aq) or
+
H2 O
Yellow Solution
Limited NH3(aq) Acid
Blue Solution
Cu(OH)2
Excess NH3(aq)
Blue Precipitate
[Cu(NH3)4(H2O)2]2
+
Deep Blue Solution
Conc. NaOH(aq) Na2CO3(aq)
Cu or S O2
KI(aq)
CuCO 3 Blue-Green Precipitate
+1
[CuCl 4]3
−
Cl
−
H2 O
[CuCl 3]2
−
Cl
White Precipitate
−
H 2O
I2
[Cu(OH)4]2
Brown Solution
Blue Solution
CuI +
[CuCl2]
CuCl
Conc. HCl −
H2 O
White Solid Insoluble
Cu 2O
Conc. HCl
Dark Greeny - Brown Solution
Red-Brown Solid Insoluble
Dil. H2SO 4
CuSO4 + Cu
H , C 2 o r r C O
Blue Solution
Red - Brown Precipitate
Cu r e p p o C f o y r t s i m e h C e h T . 3 8
N O I T C U D E R
[Cu(NH 3)2]+ 2
Colourless Solution Dil. HNO3
Cu(NO3)2 + Cu Blue Solution
HNO 3
O2
HCl(aq) or Dil. H2SO 4
N O I T A D I X O
NH3(aq)
Cu(NO3)2 + NO
0
No Reaction
Air (O2)
−
Dil. HNO3
NO 2
Cu(NO3)2 + NO Blue Solution
Brown Gas Gas
Air (O2)
NO 2 Brown Gas Gas
83. The Chemistry of Copper
Chem Factsheet
Oxides Copper forms two oxides, both of which are basic.
Copper(I) oxide, Cu2O This compound is prepared by reducing copper(II) salts in alkaline solution. Practical 3 - Preparation of copper(I) oxide Pour into a boiling tube roughly equal volumes of Feh ling’s solution A (copper(II) sulphate) and Fehling’s solution B (an alkaline solution of potassium sodium tartrate) and mix. Then add a few drops of ethanal and boil cautiously. The dark blue colour of the solution fades to give a reddish brown precipitate of copper(I) oxide. A redox reaction occurs in which ethanal is oxidised to a salt of ethanoic acid while CuII, in the form of a complex tartrate, is reduced to CuI which appears as Cu2O. Remember - This reaction is used in organic chemistry to distinguish between aldehydes and ketones. Ketones will not reduce Fehling’s Fehling’s solution because, unlike aldehydes, they are resistant to oxidation. Copper(I) oxide is a reddish brown solid which is insoluble in water but soluble in acids.
Copper(II) oxide, CuO Copper(II) oxide is a black solid that can be prepared by heating Cu(OH)2, CuCO3 or Cu(NO3)2. It is insoluble in water but dissolves in dilute acids to give solutions of CuII salts.
Practical 8 - Preparation of CuSO4.5H2O Pour dil. H2SO4 into a beaker, heat it, and add CuO with stirring until no more will dissolve. Filter off the excess CuO. Transfer the filtrate to an evaporating basin, place it on a tripod and gauze, and boil the solution until crystals show signs of forming. Turn out the heat and allow the solution to cool and crystallise. Filter off the crystals, wash them with a little deionised water, and dry. Exam Hint - ‘Crystallisation’ is different from ‘evaporation to dryness’. The latter is is not recommended recommended because: • it gives poorly poorly formed crystals; crystals; • there may not be enough water left left to act as water of crystallisation, crystallisation, resulting in the formation of anhydrous copper(II) sulphate; • impurities leave solution solution with the CuSO 4 .5H 2 O contaminating it.
Aqueous chemistry of copper(II) [Cu(H 2 O) 6 ] 2+ (aq) takes part in acid-base reactions (deprotonation) with OH -(aq) and NH 3(aq), ligand substitution with Cl (aq), precipitation with CO 32 (aq), and oxidation-reduction with I (aq).
−
Copper(I) oxide reacts with dilute sulphuric acid, dilute nitric acid and concentrated hydrochloric acid, but the products are not copper(I) sulphate, copper(I) nitrate and copper(I) chloride. Copper(I) sulphate and copper(I) nitrate disproportio disproportionate nate in water (see above), while copper(I) chloride dissolves in conc. HCl(aq) to give complex ions.
−
−
Practical 9 - CuII salts with OH-(aq) Add dilute NaOH(aq) dropwise, with shaking, to a solution of a
83. The Chemistry of Copper
Chem Factsheet
Oxides Copper(II) oxide, CuO Copper(II) oxide is a black solid that can be prepared by heating Cu(OH)2, CuCO3 or Cu(NO3)2. It is insoluble in water but dissolves in dilute acids to give solutions of CuII salts.
Copper forms two oxides, both of which are basic.
Copper(I) oxide, Cu2O This compound is prepared by reducing copper(II) salts in alkaline solution.
Practical 8 - Preparation of CuSO4.5H2O Pour dil. H2SO4 into a beaker, heat it, and add CuO with stirring until no more will dissolve. Filter off the excess CuO. Transfer the filtrate to an evaporating basin, place it on a tripod and gauze, and boil the solution until crystals show signs of forming. Turn out the heat and allow the solution to cool and crystallise. Filter off the crystals, wash them with a little deionised water, and dry.
Practical 3 - Preparation of copper(I) oxide Pour into a boiling tube roughly equal volumes of Feh ling’s solution A (copper(II) sulphate) and Fehling’s solution B (an alkaline solution of potassium sodium tartrate) and mix. Then add a few drops of ethanal and boil cautiously. The dark blue colour of the solution fades to give a reddish brown precipitate of copper(I) oxide. A redox reaction occurs in which ethanal is oxidised to a salt of ethanoic acid while CuII, in the form of a complex tartrate, is reduced to CuI which appears as Cu2O.
Exam Hint - ‘Crystallisation’ is different from ‘evaporation to dryness’. The latter is is not recommended recommended because: • it gives poorly poorly formed crystals; crystals; • there may not be enough water left left to act as water of crystallisation, crystallisation, resulting in the formation of anhydrous copper(II) sulphate; • impurities leave solution solution with the CuSO 4 .5H 2 O contaminating it.
Remember - This reaction is used in organic chemistry to distinguish between aldehydes and ketones. Ketones will not reduce Fehling’s Fehling’s solution because, unlike aldehydes, they are resistant to oxidation. Copper(I) oxide is a reddish brown solid which is insoluble in water but soluble in acids.
Aqueous chemistry of copper(II) [Cu(H 2 O) 6 ] 2+ (aq) takes part in acid-base reactions (deprotonation) with OH -(aq) and NH 3(aq), ligand substitution with Cl (aq), precipitation with CO 32 (aq), and oxidation-reduction with I (aq).
−
Copper(I) oxide reacts with dilute sulphuric acid, dilute nitric acid and concentrated hydrochloric acid, but the products are not copper(I) sulphate, copper(I) nitrate and copper(I) chloride. Copper(I) sulphate and copper(I) nitrate disproportio disproportionate nate in water (see above), while copper(I) chloride dissolves in conc. HCl(aq) to give complex ions.
−
−
Practical 9 - CuII salts with OH-(aq) Add dilute NaOH(aq) dropwise, with shaking, to a solution of a copper(II) salt. A gelatinous pale blue precipitate of hydrated copper(II) hydroxide is formed. Two protons are transferred from molecules of coordinated water to hydroxide ions: +2H +
Practical 4 - Cu2O with dilute H2SO4 Add Cu2O to dilute sulphuric acid in a test tube and warm gently. gently. A blue solution of copper(II) sulphate is formed. The reddish brown solid appears to remain unaltered, but in fact changes from Cu2O to Cu.
[Cu(H2O)6]2+(aq) + 2OH-(aq)
→
[Cu(OH)2(H2O)4](s) + 2H 2O(l)
-2H + Practical 5 - Cu2O with dilute HNO 3 Add Cu2O to dilute nitric acid in a test tube. On warming, the Cu2O dissolves to give a clear blue solution of CuSO4 plus brown fumes of NO2. Caution! These fumes are toxic. From Practical 4, a red-brown deposit of Cu might be anticipated, but Practical 1 shows that Cu dissolves in dil. HNO3.
Exam Hint - Do not show this as a precipitation reaction. All transition metal ions, and Al 3+ , react with OH -(aq) and NH 3(aq) in acid-base (deprotonation) reactions.
Divide the precipitate of copper(II) hydroxide into two portions. To one portion add concentrated NaOH(aq) and notice that it dissolves to give a blue solution containing the tetrahydroxocuprate(II) ion:
Practical 6 - Cu2O with concentrated HCl(aq) Add conc. HCl(aq) to a little Cu2O and heat to obtain a dark greenish brown solution containing various chloro-complex ions of copper(I) (p 4).
[Cu(OH)2(H2O)4](s) + 2OH-(aq)
Copper(I) oxide is also attacked by concentrated aqueous ammonia because the NH3 molecule is a ligand and can coordinate to the Cu+ ion.
→
[Cu(OH)4]2-(aq) + 4H2O(l)
Remember - Although CuO is basic, Cu(OH) 2 is amphoteric.
Heat the other portion of Cu(OH)2 and see how the colour changes from blue to black as the hydroxide de composes into the oxide:
Practical 7 - Cu2O with concentrated NH 3(aq) Add conc. NH3(aq) to a little Cu2O in a test tube, warm gently, shake carefully, and allow to stand. The solution above the unreacted Cu2O will be blue. The diamminecopper(I) ion, [Cu(NH3)2]+, is formed, but O2 from the air oxidises this to the dark blue copper(II) complex, [Cu(NH 3 )4(H 2 O) 2] 2+.
[Cu(OH)2(H2O)4](s)
→
CuO(s) + 5H2O(l)
Remember - Nearly all metal hydroxides decompose into the corresponding oxides on heating. The only ones which are stable to heat are those of the alkali metals.
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83. The Chemistry of Copper
Chem Factsheet
Practical 10 - CuII salts with NH3(aq) Add dilute NH3(aq) dropwise, with shaking, to a solution of a copper(II) salt. A gelatinous blue precipitate of hydrated copper(II) hydroxide is formed at first in an acid-base reaction: [Cu(H2O)6]2+(aq) + 2NH3(aq)
→
[Cu(OH)2(H2O)4](s) + 2NH 4+(aq)
Now add excess dil. NH3(aq). The precipitate dissolves in a ligand substitution reaction reaction to give a deep blue solution containing the the tetraamminediaquacopper(II) ion: [Cu(OH)2(H2O)4](s) + 4NH3(aq)
→
[Cu(NH3)4(H2O)2]2+(aq) + 2OH-(aq) + 2H2O(l)
Add ethanol to this solution to obtain a deposit of tiny crystals of [Cu(NH 3)4]SO4.H2O which can be filtered off and dried at room temperature. Exam Hint - The [Cu(NH 3 ) 4 (H 2 O) 2 ] 2+ ion has a distorted distorted octahedral shape. shape. NH 3 molecules surround the Cu 2+ ion in a square planar arrangement, with H 2 O molecules above and below this plane but relatively far from Cu 2+ . Never describe this this ion as ‘square planar’ because because this description description ignores the H 2 O molecules.
Copper(I) chloride, CuCl
Practical 11 - CuII salts with Cl (aq) −
Add concentrated HCl(aq) dropwise, with shaking, to a solution of a copper(II) salt. The solution changes colour from blue to green and then to yellow as a ligand substitution reaction occurs to form the tetrachlorocuprate(II) ion:
• •
[Cu(H2O)6]2+(aq) + 4Cl (aq) Blue −
¾
[CuCl4]2-(aq) + 6H2O(l) Yellow Practical 14 - Preparation of copper(I) chloride To CuSO4(aq) in a boiling tube, add conc. HCl(aq) until the solution turns yellow. yellow. This produces [CuCl4]2-. Add a few few pieces of copper foil and boil for a few minutes until the solution changes colour to a dark greenish brown. [CuCl4]2- becomes reduced to chloro-complexes of copper(I), e.g.
The reaction is reversible. Add water to the [CuCl4]2- solution and notice that the colour changes back to green and then to blue. Practical 12 - CuII salts with CO32-(aq) Add Na2CO3(aq) dropwise, with shaking, to a solution of a copper(II) salt until the the reagent is eventually present in excess. Blue-green copper(II) carbonate, which does not dissolve in exce ss Na2CO3(aq), is formed in a precipitation reaction: Cu2+(aq) + CO32-(aq)
[CuCl4]2-(aq) + Cu(s)
Remember • With Na2CO3(aq), all M 2+(aq) ions give a precipitate of the metal carbonate, MCO 3. M 3+(aq) ions, in contrast, give a precipitate of the metal hydroxide, M(OH)3 , plus effervescence due to CO 2(g). • Pr Prec ecip ipit itat ates es fo form rmed ed wi with th Na2CO3(aq) never dissolve in excess reagent.
Cl
−
−
→
−
•
−
→
Cu+ I + I −
(2I
→
H2 O
Cl
−
[CuCl3]2-
H 2O
[CuCl4]3-
Exam Hint - Do not confuse the tetrachloro-complexes of copper(I) and copper(II). They have different charges and different colours. Cu I : [ CuC l4 ] 3- Dark greenish brown II Cu : [ CuC l4 ] 2- Yellow
2CuI(s) + I 2(aq)
Remember • The produ product ct is coppe copper(I r(I)) iodide; iodide; not not copper copper(II (II)) iodide iodide.. • Cop Copper per(II (II)) iodide iodide does does not not exist exist.. If it it did, did, it would would dec decompo ompose se into copper(I) iodide and iodine by electron transfer from anion to cation: Cu++ I I
H2O
Cl
−
[CuCl2]-
At high concentrations of Cl- the dominant ion is [CuCl4]3-. At low concentrations of Cl- equilibrium is disturbed to the left hand side. Add water to the dark brown solution and see the reprecipitation of CuCl.
Practical 13 - CuII salts with I-(aq) Add KI(aq) to a solution of a copper(II) salt, shake and allow to stand. A white precipitate of copper(I) iodide settles underneath a brown solution of iodine. A redox reaction occurs in which Cu2+ oxidises I to I2, and is itself reduced to Cu +: −
2[CuCl2]-(aq)
Practical 15 - CuCl with conc. HCl(aq) Add conc. HCl(aq) to CuCl and shake. shake. The white solid dissolves to give a dark greenish brown solution containing three comple x ions of copper(I) in equilibrium with one a nother. CuCl
2Cu2+(aq) + 4I (aq)
→
Now pour the contents of the tube into cold water in a beaker. This decomposes the chloro-complexes (see below) to give a white precipitate of CuCl that can be filtered off, washed and dried.
CuCO3(s)
→
Copper(I) Copper (I) chlo chlorid ridee is prepar prepared ed by redu reducin cing g [CuCl [CuCl4] 2- with Cu or SO 2. It dissolv dissolves es in conc. HCl(a HCl(aq) q) to give a serie seriess of chloro chloro-compl -complexes. exes.
I 2)
The same same applies applies to any other salt (e.g. iron(I iron(III) II) iodide) consis consisting ting of a cation that is easily reduced reduced and an anion that is easily oxidised.
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83. The Chemistry of Copper
Chem Factsheet
Questions 1
Devise a simple simple test, not requiring requiring laborator laboratory y reagents, reagents, for distinguishi distinguishing ng between solutions solutions containi containing ng [CuCl4]2- and [CuCl4]3- ions. State what you would observe in each case.
2
Thiss quest Thi question ion conc concern ernss the the follo followin wing g ions: ions: [Cu(H [Cu(H2O)6]2+ and [CuCl4]2A B (a) Name A and B. A and B. (b) State the colours of of A (c) State the shapes of of A A and B. (d) Explain the difference in coordination numbers.
3
compoundX. At the same U, V and W are three dark coloured solids, insoluble in water. They all dissolve in dilute nitric acid to give a blue solution of compoundX time U and W evolve brown fumes but V does not do so. With concentrated hydrochloric acid,U acid, U does not dissolve, but V dissolves to give a green solution Y and W dissolves to to give a greenish brown solution Z. (a)) Id (a Ident entif ify y U, V and W. (b) Name the blue compound X. (c) Write a balanced balanced equation, equation, with state symbols, symbols, for for V dissolving in dilute nitric acid. (d) Write down the formu formulae lae of all copper containing ions in solutions Y and Z.
4
Suggestt why, Sugges why, when copper(I) copper(I) chloride chloride is shaken with with water, water, the aqueous aqueous extract extract is green. green.
5
Explain why copper(II copper(II)) sulphate-5-wate sulphate-5-waterr is coloured, although although copper(I) copper(I) sulphate sulphate and anhydrous anhydrous copper(II) copper(II) sulphate sulphate are both colourless. colourless.
. r u c c o t o n n a c n o i t o m o r p , t e s r e p p u e h t n i s e i c n a c a v o n e r a e r e h t f I . d e i p u c c o 2 y l l u f s l a t i b r o d 3 s t i l l a s a h 4 O S u C n i n o i + u C e h T . s l a t i b r o - d e h t f o g n i t t i l p s o n s i e r e h t o s , ) s d n a g i l o n ( s n o i + 2 u C e l p m i s s n i a t n o c 4 O S u C s u o r d y h n A 2 4 4 2 . n e e r g d n a e u l b s t i m s n a r t t u b s e i c n e u q e r f w o l l e y d n a d e r e h t s b r o s b a O H 5 . O S u C n i + 2 ] ) O H ( u C [ . d e r u o l o c s r a e p p a e r o f e r e h t d n a s e i c n e u q e r f e s e h t n i t n e i c i f e d s i t h g i l d e t t i m s n a r T . t e s r e p p u e h t o t r e w o l e h t m o r f s n o r t c e l e g n i t o m o r p n i d e b r o s b a e b n a c t h g i l e t i h w f o s e i c n e u q e r f n i a t r e C . t e s r e p p u e h t n i o w t d n a t e s y g r e n e r e w o l e h t n i s l a t i b r o e e r h t e r a e r e h T . s l a t i b r o - d f o s t e s o w t o t n i s d n a g i l y b t i l p s e r a s n o r t c e l e d 3 5 . I I u C o t I u C f o n o i t a d i x o e h t s t s i s s a r i a e h t m o r f 2 O . ) w o l l e y ( - 2 ] 4 l C u C [ e m o s s e v i g , - l C h t i w , h c i h w ) e u l b ( + 2 ] ) O H ( u C [ g n i v i g s e t a n o i t r o p o r p s i d + u C . - l C d n a + u C g n i n i a t n o c n o i t u l o s a e v i g o t y l t h g i l s s e v l o s s i d l C u C 4 6
2
2 . - 2 ] 4 l C u C [ d n a - 2 ] 3 l C u C [ , - ] 2 l C u C [ s n i a t n o c Z . - 2 ] 4 l C u C [ d n a + 2 ] 6 ) O H ( u C [ s n i a t n o c Y ) d ( 2 2 3 3 ) l ( O H + ) q a ( ) O N ( u C → ) q a ( O N H 2 + ) s ( O u C ) c ( e t a r t i n ) I I ( r e p p o C ) b ( 2 O u C = W O u C = V u C = U ) a ( 3
2 . n o i t a c + 2 u C l l a m s e h t d n u o r a d e k c a p e b n a c m e h t f o r e w e f d n a e l u c e l o m O H e h t n a h t d n a g i l r e g r a l a s i n o i - l C e h T ) d ( . l a r d e h a r t e t s i B . l a r d e h a t c o d e t r o t s i d / l a r d e h a t c o s i A ) c ( . w o l l e y s i B . e u l b s i A ) b ( ) I I ( e t a r p u c o r o l h c a r t e t = B ) I I ( r e p p o c a u q a a x e h = A ) a ( 2
. e t a t i p i c e r p e t i h w a s e v i g - 3 ] 4 l C u C [ f o n o i t u l o S . e u l b n e h t d n a n e e r g o t r u o l o c s e g n a h c - 2 ] 4 l C u C [ f o n o i t u l o S . r e t a w d d A 1 s r e w s n A
Acknowledgements: This Factsheet was researched and written by John Brockington. Curriculum Press, Bank House, 105 King Street, Wellington, Shropshire, TF1 1NU. ChemistryFactsheets may be copied free of charge by teaching staff or students, provided that their school is a registered subscriber. No part of these Factsheets may be reproduced, stored in a retrieval system, or transmitted, in any other form or by any other means, without the prior permission of the publisher. ISSN 1351-5136
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