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transition metal chemistry of nickel complexes oxidation state +2 redox chemical reactions physical properties advanced inorganic chemistry of nickel

Revision notes on 3d block Transition Metals chemistry of nickel

for Advanced A Level Inorganic Chemistry students

green octahedral shape complex of hexaaquanickel(II) ion Ni2+(aq) [Ni(H2O)6]2+(aq) oxidation state +2

pale blue octahedral complex of hexaamminenickel(II) ion [Ni(NH3)6]2+(aq) oxidation state +2Periodic Table - Transition Metals - 3d block Nickel Chemistry - Doc Brown's Chemistry  Revising Advanced Level Inorganic Chemistry Periodic Table Revision Notes

Part 10. Transition Metals 3d–block

10.10 Nickel Chemistry

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All my periodic table (3d-block) advanced level chemistry revision study notes

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GCSE Level Notes on Transition Metals (for the basics)

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The chemistry of nickel is dominated by the +2 oxidation state with many nickel(II) complexes known.

The principal oxidation states of nickel are described via redox reactions of nickel, ligand substitution displacement reactions of nickel, balanced equations of nickel chemistry, formula of nickel complex ions, shapes colours of nickel complexes, formula of compounds.

See also the absorption spectra and colours of nickel compounds   *   [WEBSITE SEARCH BOX]

10.10. Chemistry of Nickel Ni, Z=28, 1s22s22p63s23p63d84s2 

data comparison of nickel with the other members of the 3d–block and transition metals

Z and symbol 21 Sc 22 Ti 23 V 24 Cr 25 Mn 26 Fe 27 Co 28 Ni 29 Cu 30 Zn
property\name scandium titanium vanadium chromium manganese iron cobalt nickel copper zinc
melting point/oC 1541 1668 1910 1857 1246 1538 1495 1455 1083 420
density/gcm–3 2.99 4.54 6.11 7.19 7.33 7.87 8.90 8.90 8.92 7.13
atomic radius/pm 161 145 132 125 124 124 125 125 128 133
M2+ ionic radius/pm na 90 88 84 80 76 74 72 69 74
M3+ ionic radius/pm 81 76 74 69 66 64 63 62 na na
common oxidation states +3 only +2,3,4 +2,3,4,5 +2,3,6 +2,3,4,6,7 +2,3,6 +2,3 +2,+3 +1,2 +2 only
outer electron config. [Ar]... 3d14s2 3d24s2 3d34s2 3d54s1 3d54s2 3d64s2 3d74s2 3d84s2 3d104s1 3d104s2
Elect. pot. M(s)/M2+(aq) na –1.63V –1.18V –0.90V –1.18V –0.44V –0.28V –0.26V +0.34V –0.76V
Elect. pot. M(s)/M3+(aq) –2.03V –1.21V –0.85V –0.74V –0.28V –0.04V +0.40 na na na
Elect. pot. M2+(aq)/M3+(aq) na –0.37V –0.26V –0.42V +1.52V +0.77V +1.87V na na na

Elect. pot. = standard electrode potential data for nickel (EØ at 298K/25oC, 101kPa/1 atm.)

na = data not applicable to nickel

Extended data table for NICKEL

property of nickel/unit value for Ni
melting point Ni/oC 1455
boiling point Ni/oC 2730
density Ni/gcm–3 8.90
1st Ionisation Energy Ni/kJmol–1 737
2nd IE/kJmol–1 1753
3rd IE/kJmol–1 3393
4th IE/kJmol–1 5300
5th IE/kJmol–1 7280
atomic radius Ni/pm 125
Ni2+ ionic radius/pm 72
Relative polarising power Ni2+ ion 2.8
Ni3+ ionic radius/pm 62
Relative polarising power Ni3+ ion 4.8
oxidation states of Ni, less common/stable +2, +3
simple electron configuration of Ni 2,8,16,2
outer electrons of Ni [beyond argon core] [Ar]3d84s2
Electrode potential Ni(s)/Ni2+(aq) –0.26V
Electrode potential Ni(s)/Ni3+(aq) na
Electrode potential Ni2+(aq)/Ni3+(aq) na
Electronegativity of Ni 1.91


  • Uses of NICKEL

    • Nickel is a moderately hard silvery–white metal, lustrous like most transition metals and malleable and ductile.

    • Nickel is quite resistant to corrosion and not affected by water but will dissolve slowly in most strong acids.

    • Nickel has many uses from 'silver' coinage metals like cupro–nickel, which is an alloy of nickel and copper that doesn't readily corrode.

    • Along with chromium, nickel is used in stainless steels.

    • Alnico alloy (Al + Ni + Co) is used to make permanent magnets.

    • Nichrome wire (Ni + Cr) is used to make wire for windings in electric motors.

    • Nickel is a constituent of monel metal alloy used to make ships propeller shafts and chemical reactor vessels because of its strength and anti–corrosion properties.

    • Nickel is an important hydrogenation catalyst in converting unsaturated vegetable oils to saturated fats like margarine.

      • unsaturated oil + hydrogen ==> low melting solid more saturated fat

      • Along the carbon chain of the vegetable oil you get: –CH=CH– + H2 ===> –CH2–CH2

      • This reaction is described in detail at the end of my nickel notes.

    • Solutions of nickel(II) salts or complexes are used in electroplating nickel onto other metal surfaces.

      • e.g. the complex ion salt Ni(NH4)2(SO4)2.6H2O

    • Nickel(II) oxide, NiO, is used in pigments.

  • Biological role of nickel

    • It is apparently found in human tissue, but its role is unknown.

The Chemistry of NICKEL

Pd s block d blocks (3d block nickel) and f blocks of metallic elements p block elements
Gp1 Gp2 Gp3/13 Gp4/14


2 3Li 4Be Part of the modern Periodic Table of Elements: ZSymbol, z = atomic or proton number

Sc to Zn are now considered the head-top elements of groups 3 to 12

3d block of metallic elements: Scandium to Zinc focus on nickel

5B 6C
3 11Na 12Mg 13Al 14Si
4 19K 20Ca 21Sc







 [Ar] 3d34s2



[Ar] 3d54s1



   [Ar]   3d54s2



[Ar] 3d64s2



[Ar] 3d74s2



[Ar] 3d84s2



[Ar] 3d104s1



[Ar] 3d104s2


31Ga 32Ge
5 37Rb 38Sr 39Y 40Zr 41Nb 42Mo 43Tc 44Ru 45Rh 46Pd 47Ag 48Cd 49In 50Sn
6 55Cs 56Ba 57,58-71 72Hf 73Ta 74W 75Re 76Os 77Ir 78Pt 79Au 80Hg 81Tl 82Pb
7 87Fr 88Ra 89,90-103 104Rf 105Db 106Sg 107Bh 108Hs 109Mt 110Ds 111Rg 112Cn 113Nh 114Fl

Summary of oxidation states of the 3d block metals (least important) Ti to Cu are true transition metals

Sc Ti V Cr Mn Fe Co Ni Cu Zn
  (+2) (+2) (+2) +2 +2 +2 +2  (3d8) +2 +2
+3 +3 +3 +3 (+3) +3 +3 (+3)  (3d7) (+3)  
  +4 +4   +4     (+4)  (3d6)    
      +6 (+6) (+6)        
3d14s2 3d24s2 3d34s2 3d54s1 3d54s2 3d64s2 3d74s2 3d84s2 3d104s1 3d104s2
The outer electron configurations beyond [Ar] and the (ground state of the simple ion)

Note that when 3d block elements form ions, the 4s electrons are 'lost' first.

The oxidation states and electron configuration of nickel in the context of the 3d block of elements

electrode potential chart diagram for nickel oxidation states Ni 0 +2

The electrode potential chart highlights the values for various oxidation states of nickel.

The electrode potentials involving nickel ions correspond to hydrated complex ions where the ligands are water, oxide or hydroxide.

If you change either the ligand or the oxidation state, will also change the electrode potential for that half-reaction involving a nickel ion.


  • Electron configuration of Ni2+ is [Ar]3d8

  • In aqueous solution nickel forms the green stable hexaaquanickel(II) ion, [Ni(H2O)6]2+(aq) from eg nickel(II) chloride solution NiCl2(aq) or nickel(II) sulfate NiSO4(aq), both of which are suitable for laboratory experiments for investigating the aqueous chemistry of the nickel(II) ion.

  •   emphasising the octahedral shape of the [Ni(H2O)6]2+ ion or octahedral arrangement of dative covalent bonds in the hexaaquanickel(II) ion Ni2+(aq) [Ni(H2O)6]2+(aq) oxidation state +2 bond angles of 90 and 180  emphasising the six dative covalent bonds between the lone electron pair donating ligand and the central metal ion.

  • With alkalis sodium hydroxide or ammonia, nickel(II) ions produce the hydrated nickel(II) hydroxide green? precipitate. There is no further reaction with excess of NaOH, but see further down for excess NH3.

    • Ni2+(aq)  +  2OH(aq) ===>  Ni(OH)2(s) 

      • This precipitation reaction can be written as

      • [Ni(H2O)6]2+(aq) +  2OH(aq) ===>  [Ni(OH)2(H2O)4](s)  +  2H2O(l)

      • The two nickel(II) complexes are octahedral in shape with a co-ordination number of 6 from 6 unidentate ligands.

      • The overall charge on the nickel(II) hydroxide precipitate complex is zero, the 2OH- cancelling out the Ni2+.

      • This is an example of a nickel complex ligand exchange reaction, two hydroxide ions displacing two water molecules.

      • Water and the hydroxide ion are monodentate (unidentate ligands), that is each ligand can donate a single pair of electrons to form one co-ordinate bond (dative covalent bond).

      • In most ligand exchange reactions there is no change in oxidation state unless a reducing agent or oxidising agent is present.

      • Transition metal commonly form octahedral complexes, like those of nickel, with small ligands like water, ammonia and hydroxide ion.

  • With alkaline aqueous sodium carbonate solutions, nickel(II) ions produces a precipitate of green ppt. of nickel(II) carbonate.

    • Ni2+(aq) + CO32–(aq) ===> NiCO3(s) 

      • Its actually a basic carbonate – a mixture of the hydroxide and carbonate, you can make the pure carbonate by using sodium hydrogencarbonate solution.

      • Ni2+(aq) + 2HCO3(aq) ===> NiCO3(s) + 4H2O(l) + CO2(g)

  • VIEW more on ppts. with OH, NH3 and CO32–, and complexes, if any, with excess reagent.

  • With excess aqueous ammonia the blue hexaammine complex ion is formed from the hexaaquanickel(II) ion – a typical ligand substitution reaction giving the hexaamminenickel(II) ion:

  • [Ni(H2O)6]2+(aq) + 6NH3(aq) [Ni(NH3)6]2+(aq) + 6H2O(l)

    • See also the absorption spectra and colours of nickel compounds

    • The two nickel(II) complexes are octahedral in shape with a co-ordination number of 6.

    • The overall charge on the nickel(II) hydroxide complex remains 2+ because both ligands are electrically neutral.

    • This is another example of a nickel complex ligand exchange reaction where six ammonia molecules replace six water molecules.

    • Kstab = [[Ni(NH3)6]2+(aq)] / [[Ni(H2O)6]2+(aq)] [NH3(aq)]6

    • Kstab = 4.8 x 107 mol–6 dm18  [lg(Kstab) = 7.7]

    • You can also write the equation of the ammine complex from the dissolving of nickel(II) hydroxide precipitate.

      • Ni(OH)2(s) + 6NH3(aq) [Ni(NH3)6]2+(aq) + 2OH(aq)

    • Ligand substitution may be incomplete, so, with lower concentrations of ammonia the pale blue complex can also have other structures e.g. [Ni(H2O)2(NH3)4]2+(aq)   and [Ni(H2O)4(NH3)2]2+(aq) 

      • Both of these octahedral complex ions exhibit E/Z (cis/trans) isomerism, diagrams below)

  • The hexaaquanickel(II) ion also forms complexes with other amine ligands

    • e.g. the bidentate ligand 1,2–diaminoethane (H2N–CH2–CH2–NH2), often abbreviated to en from its old trivial name of ethylenediamine). Each of the lone pairs of electrons on the nitrogen atoms can form a co-ordinate bond

    • R/S optical isomers of the nickel(II) complex ion with 1,2-diaminoethane [Ni(en)3]2+[Ni(H2O)6]2+(aq) + 3en(aq) [Ni(en)3]2+(aq) + 6H2O(l)

      • This is an example of a chelation substitution reaction where a bidentate or multidentate ligand displaces a numerically greater monodentate (unidentate) ligands.

      • The resulting nickel complex is described as an example of a chelate.

      • Kstab = [[Ni(en)3]2+(aq)] / [[Ni(H2O)6]2+(aq)] [[en(aq)]3]

      • Kstab = 2.0 x 1018 mol–3 dm9 [lg(Kstab) = 18.3]

      • The reaction is almost completely 100% to the right.

      • Notice that the Kstab is greater than the Kstab for the formation of the ammonia complex, so you can correctly predict that the following ligand exchange will take place ...

      • [Ni(NH3)6]2+(aq) + 3en(aq) [Ni(en)3]2+(aq)  +  6NH3(aq)

      • I've used en for simplicity, but the formula of the complex ion formed is [Ni(H3NCH2CH2NH3)3]2+

      • Although then enthalpy changes for these reactions are similar, because a similar number of similar covalent bonds are broken or made, the release of the larger number of smaller molecules leads to a large increase in entropy (a large positive ΔS).

      • This makes the free energy change, calculated from ΔG = ΔH - TΔS, more negative, therefore more feasible for these nickel complex reactions.

  • The complex with EDTA is also readily formed.

    • EDTA is an even more powerful chelating agent with an extremely high Kstab values.

    • [Ni(H2O)6]2+(aq) +  EDTA4–(aq) [Ni(EDTA)]2–(aq) + 6H2O(l)

    • Kstab = [[Ni(EDTA)3]2–(aq)] / [[Ni(H2O)6]2+(aq)] [[EDTA4–(aq)]]

    • Kstab = 1.0 x 1019 mol–1 dm3 [lg(Kstab) = 19.0]

    • Remember [H2O] is not included in these equilibrium expressions.

    • Note that Kstab for the same ion tends to increase the greater the chelating power of an individual ligand in terms of the ligand bond formed – mainly due to the increase in entropy as more ligand particles are displaced by the polydentate ligands displacing the unidentate ligands.

    • e.g. for the same nickel(II) ion Kstab(EDTA) > Kstab(en) > Kstab(NH3)

    • That is from left to right in the sequence, the entropy change decreases, multidentate > bidentate > monodentate (unidentate)

structure of the complex ion [NiEDTA]2- formed between the aqueous nickel(II) ion, Ni2+(aq) and the EDTA anion [EDTA]4-

The structure of the complex ion [NiEDTA]2- formed between the aqueous nickel(II) ion, Ni2+(aq) and the EDTA anion [EDTA]4-

The process is called a chelation of the central nickel(II) ion.

  • Other complexes of nickel

    • nickel carbonyl Ni(CO)4 colourless tetrahedral shape moleculeNickel carbonyl, Ni(CO)4,

      • Note

      • (i) Nickel carbonyl is a neutral complex i.e. you can write it as [Ni(CO)4]0

      • (ii) It is a tetrahedrally shaped covalent molecule with a OC-N-CO bond angle of 109.5o..

      • (i) nickel is in a zero oxidation state and the compound is a colourless liquid.

      • (ii) the ligand CO also acts as ligand with haemoglobin (hemoglobin) in carbon monoxide poisoning.

        • The carbon monoxide can act as a lone pair donor ligand :CO

    • Ni2+ forms the tetrachloronickelate(II) ion, [NiCl4]2–, a tetrahedral anionic complex with the chloride ion ligand (Cl).

      • [Ni(H2O)6]2+(aq) +  4Cl(aq) [NiCl4]2–(aq)  +  6H2O(l)

      • terachloronickelate(II) complex ion [NiCl4]2- colourless tetrahedral shape aniobic complex of oxidation state +2 of nickelIn this ligand exchange reaction, the nickel(II) complex ion shape changes from octahedral to tetrahedral, the co-ordination number changes from 6 to 4, but the oxidation state of nickel remains at +2. The overall electrical charge on the chloro complex is 2- (from 2+/+2 and 4x-1).

      • Its likely that the more bulky chloride ion (radius Cl > C) 'forces' the formation of the tetrahedral shape rather than a square planar shaped complex in the reaction described below.

      • Kstab = [[NiCl4]2–(aq)] / [[Ni(H2O)6]2+(aq)] [Cl(aq)]4

      • Kstab = ? mol4 dm–12 

      • lg(Kstab) = ?

    • Ni2+ forms the tetracyanonickelate(II) ion, [Ni(CN)4]2–, a square planar anionic complex with the cyanide ion (the ligand structure is :CN).

      • [Ni(H2O)6]2+(aq) + 4CN(aq) [NiCN4]2–(aq) + 6H2O(l)

      • Similar to above, in this ligand exchange reaction, the nickel(II) complex ion shape changes from octahedral to square planar, the co-ordination number changes from 6 to 4, but the oxidation state of nickel remains at +2. The overall electrical charge on the chloro complex is 2- (from 2+/+2 and 4x-1).

      • Kstab = [[NiCN4]2–(aq)] / [[Ni(H2O)6]2+(aq)] [CN(aq)]4

      • Kstab = 2 x 1031 mol4 dm–12 

      • lg(Kstab) = 31.3

  • Summary of some complexes–compounds & oxidation states of nickel compared to other 3d–block elements


Nickel(III) and nickel(IV) oxidation state chemistry

 Higher oxidation state compounds of nickel can ve stabilised by electronegative elements like oxygen or fluorine.

e.g. nickel(III) oxide, Ni2O3, a grey-black solid

nickel(III) fluoride, NiF3, forms complex ions e.g. the hexafluoronickelate(III) ion, [NiF6]3- in the salt K3NiF6

The nickel(IV) oxidation state occurs in the salt K2NiF6 which contains the hexafluoronickelate(II) ion, [NiF6]2-



An example of the catalytic action of nickel metal.

  • nickel catalyst for hydrogenation of unsaturated alkenes vegetable oils to a more saturated molecule

    • An example of nickel acting as a heterogeneous catalysis is illustrated above, the hydrogenation of alkenes (e.g. ethene + hydrogen ===> ethane). 

    • Hydrogenation is an extremely important process in the food industry or converting unsaturated oils into low melting hydrogenated solid fats to make the more spreadable margarine.

    • For more details see Natural esters - triglyceride fats and oils, manufacture of margarine and biodiesel

    • Nickel is the solid phase catalyst and the reactant gases in the different gaseous phase.

    • In terms of activation energies, with reference to the reaction profile below:

      • (1) ==> (2) is represented by Ea1, the absorption of the reactant molecules onto the catalyst surface to form the intermediate state between nickel and the adsorbed gases..

      • (3) represents the minimum potential energy trough where the molecules are adsorbed onto the catalyst surface.

      • (2) ==> (3-5) is represented by Ea2 the formation of the products form the intermediate adsorbed states of the molecules.

      • reaction profile for the catalytic hydrogenation of an alkene unsaturated molecule to a saturated molecule

      • The red line represents the catalysed reaction profile (the catalysed pathway)

      • The blue line represents the uncatalysed reaction profile (the uncatalysed pathway)

      • A two stage reaction profile for a catalytic cycle (Ea = activation energy)

        • This sort of diagram is most applicable to homogeneous catalysis where definite intermediates are formed, but in general principle it applies to heterogeneous catalysis too where the adsorption (particularly chemical) is equivalent to forming a transition state or complex.

        • Ea1 is the activation energy leading to the formation of an intermediate complex between nickel and the adsorbed gases.

        • Ea2 is the activation energy for the change of the intermediate complex into product (ethane).

        • Ea3 is the activation energy of the uncatalysed reaction between nickel and hydrogen.

physical and chemical properties of the 3d block transition metal nickel, oxidation and reduction reactions of nickel ions, outer electronic configurations of nickel, principal oxidation states of nickel, shapes of nickel's complexes, octahedral complexes of nickel, tetrahedral complexes of nickel, square planar complexes of nickel, stability data for nickel's complexes, aqueous chemistry of nickel ions, redox reactions of nickel ions, physical properties of nickel, melting point of nickel, boiling point of nickel, electronegativity of nickel, density of nickel, atomic radius of nickel, ion radius of nickel, ionic radii of nickel's ions, common oxidation states of nickel, standard electrode potential data for nickel, ionisation energies of nickel, polarising power of nickel ions, industrial applications of nickel compounds, chemical properties of nickel compounds, why are nickel complexes coloured?, isomerism in the complexes of nickel, formulae of nickel compounds, tests for nickel ions keywords redox reactions ligand substitution displacement balanced equations formula complex ions complexes ligand exchange reactions redox reactions ligands colours oxidation states: nickel ions Ni(0) Ni2+ Ni(+2) Ni(II) NiCl2 NiSO4 Ni2+ + 2OH– ==> Ni(OH)2 Ni2+ + CO32– ==> NiCO3 Ni2+ + 2HCO3– ==> NiCO3 + 4H2O + CO2 [Ni(H2O)6]2+ + 6 NH3 [Ni(NH3)6]2+ + 6H2O [Ni(H2O)6]2+ + 6NH3 ==> [Ni(NH3)6]2+ + 6 H2O Kstab = [[Ni(NH3)6]2+] / [[Ni(H2O)6] 2+] [NH3]6 Ni(OH)2 + 6NH3 [Ni(NH3)6]2+ + 2OH– [Ni(H2O)6]2+ + 3en ===> [Ni(en)3]2+ + 6H2O Kstab = [[Ni (en)3]2+] / [[Ni(H2O)6]2+] [[en]3] [Ni(H2O)6]2+ + EDTA4– ===> [Ni(EDTA)]2– + 6H2O Kstab = [[Ni(EDTA)3]2–] / [[Ni (H2O)6]2+] [[EDTA4–]][Ni(H2O)6]2+ + 4 Cl– ==> [NiCl4]2– + 6H2O Kstab = [[NiCl4]2–] / [[Ni(H2O)6]2+] [Cl–]4 [Ni(H2O)6]2+ + 4 CN– ==> [NiCN4]2– + 6H2O Kstab = [[NiCN4]2–] / [[Ni(H2O)6]2+] [CN–]4 Kstab = 2 x 1031 mol4 dm–12 [lg(Kstab) = 31.3] oxidation states of nickel, redox reactions of nickel, ligand substitution displacement reactions of nickel, balanced equations of nickel chemistry, formula of nickel complex ions, shapes colours of nickel complexes  Na2CO3 NaOH NH3 nickel chemistry for AQA AS chemistry, nickel chemistry for Edexcel A level AS chemistry, nickel chemistry for A level OCR AS chemistry A, nickel chemistry for OCR Salters AS chemistry B, nickel chemistry for AQA A level chemistry, nickel chemistry for A level Edexcel A level chemistry, nickel chemistry for OCR A level chemistry A, nickel chemistry for A level OCR Salters A level chemistry B nickel chemistry for US Honours grade 11 grade 12 nickel chemistry for pre-university chemistry courses pre-university A level revision notes for nickel chemistry  A level guide notes on nickel chemistry for schools colleges academies science course tutors images pictures diagrams for nickel chemistry A level chemistry revision notes on nickel chemistry for revising module topics notes to help on understanding of nickel chemistry university courses in science careers in science jobs in the industry laboratory assistant apprenticeships technical internships USA US grade 11 grade 11 AQA A level chemistry notes on nickel chemistry Edexcel A level chemistry notes on nickel chemistry for OCR A level chemistry notes WJEC A level chemistry notes on nickel chemistry CCEA/CEA A level chemistry notes on nickel chemistry for university entrance examinations biological role of cobalt nickel is unknown, nickel(II) chemistry, shape and formula of complexes of nickel(II) Ni2+, complexes of nickel with ammonia, oxidation of nickel(II) ion Ni2+ to the nickel(III) ion Ni3+, reactions of the nickel(II) ion Ni2+ with hydroxide ion, structure formula and shape of nickel carbonyl, colour and structure of nickel(III) Ni3+ complexes, formula of EDTA complexes of nickel, tetrahedral complexes of nickel with chloride ion ligands, octahedral complexes of nickel(II) ion Ni2+ with cyanide and water ligands, octahedral complexes of nickel(III) Ni3+


GCSE Level Notes on Transition Metals (for the basics)

The chemistry of Scandium * Titanium * Vanadium * Chromium * Manganese

The chemistry of Iron * Cobalt * Nickel * Copper * Zinc * Silver & Platinum

Introduction 3d–block Transition Metals * Appendix 1. Hydrated salts, acidity of hexa–aqua ions * Appendix 2. Complexes & ligands * Appendix 3. Complexes and isomerism * Appendix 4. Electron configuration & colour theory * Appendix 5. Redox equations, feasibility, Eø * Appendix 6. Catalysis * Appendix 7. Redox equations * Appendix 8. Stability Constants and entropy changes * Appendix 9. Colorimetric analysis and complex ion formula * Appendix 10 3d block – extended data * Appendix 11 Some 3d–block compounds, complexes, oxidation states & electrode potentials * Appendix 12 Hydroxide complex precipitate 'pictures', formulae and equations Some pages have a matching sub-index

Advanced Level Inorganic Chemistry Periodic Table Index: Part 1 Periodic Table history Part 2 Electron configurations, spectroscopy, hydrogen spectrum, ionisation energies * Part 3 Period 1 survey H to He * Part 4 Period 2 survey Li to Ne * Part 5 Period 3 survey Na to Ar * Part 6 Period 4 survey K to Kr AND important trends down a group * Part 7 s–block Groups 1/2 Alkali Metals/Alkaline Earth Metals * Part 8  p–block Groups 3/13 to 0/18 * Part 9 Group 7/17 The Halogens * Part 10 3d block elements & Transition Metal Series * Part 11 Group & Series data & periodicity plots All 11 Parts have their own sub-indexes near the top of the pages

Group numbering and the modern periodic table

The original group numbers of the periodic table ran from group 1 alkali metals to group 0 noble gases. To account for the d block elements and their 'vertical' similarities, in the modern periodic table, groups 3 to group 0 are numbered 13 to 18. So, the p block elements are referred to as groups 13 to group 18 at a higher academic level, though the group 3 to 0 notation is still used, but usually at a lower academic level. The 3d block elements (Sc to Zn) are now considered the head (top) elements of groups 3 to 12.

Website content © Dr Phil Brown 2000+. All copyrights reserved on revision notes, images, quizzes, worksheets etc. Copying of website material is NOT permitted. Doc Brown's Chemistry theoretical-physical chemistry revision notes for pre-university level students on d-block elements including the physical and chemical properties reactions equations and trends explained for the 3d-block of transition metals series