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3d block Transition Metals chemistry of nickel for Advanced level pre-university inorganic chemistry students

Doc Brown's advanced A level inorganic chemistry exam revision notes

green octahedral shape complex of hexaaquanickel(II) ion Ni2+(aq) [Ni(H2O)6]2+(aq) oxidation state +2Inorganic chemistry Part 10. Transition Metals 3d–block

10.10 Revision notes on Nickel Chemistry including oxidation states and complex ions

[Author ©  Dr Phil Brown PhD: Doc Brown's Chemistry exam revision notes suitable for students of advanced pre-university A level inorganic chemistry for AQA, Edexcel, OCR, Salters, WJEC, CCEA, IB and US grade 11-12 courses: Periodic Table - 3D block and 1st transition metal series: the chemistry of nickel and its compounds [page updated May 4th 2026 *]

Sub-index for this page on the chemistry of nickel - a 3d block transition element

1. Introduction to the chemistry of nickel

2. Data tables for the chemistry of nickel

3. Uses of nickel

4. Electron configuration, oxidation states and electrode potentials

5. Nickel(II) chemistry and complexes

6. Brief mention of nickel(III) and nickel(IV) chemistry

7. An example of the heterogeneous catalytic action of nickel metal - hydrogenation

8. The vertical connection of nickel with the other d-block elements of Group 10 (IUPAC designation)

9. Learning objectives for the chemistry of nickel

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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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1. Introduction to the chemistry of nickel - a 3d block transition element

Nickel is the head-top element of Group 10 of the periodic table (modern IUPAC assignment).

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.

Nickel is ferromagnetic, meaning it is a strongly magnetisable material that retains its magnetism without the need of an external magnetic field.

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

2. Data for 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
EØ M(s)/M2+(aq) na –1.63V –1.18V –0.90V –1.18V –0.44V –0.28V –0.26V +0.34V –0.76V
EØ M(s)/M3+(aq) –2.03V –1.21V –0.85V –0.74V –0.28V –0.04V +0.40 na na na
EØ 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

3. 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.

4. The Chemistry of NICKEL - electron configuration, oxidation states and electrode potentials

Pd s block d blocks (3d block nickel) and f blocks of metallic elements p block elements
Gp1 Gp2 Gp3/13 Gp4/14
1

1H
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]3d14s2

scandium

 22Ti

[Ar]3d24s2

titanium

 23V

 [Ar] 3d34s2

vanadium

 24Cr

[Ar] 3d54s1

chromium

 25Mn

   [Ar]   3d54s2

manganese

 26Fe

[Ar] 3d64s2

iron

 27Co

[Ar] 3d74s2

cobalt

 28Ni

[Ar] 3d84s2

nickel

 29Cu

[Ar] 3d104s1

copper

 30Zn

[Ar] 3d104s2

zinc

 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
Group 3 Group 4 Group 5 Group 6 Group 7 Group 8 Group 9 Group 10 Gp 11 Group 12
Sc Ti V Cr Mn Fe Co Ni Cu Zn
                +1  
  (+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)    
    +5              
      +6 (+6) (+6)        
        +7          
3d14s2 3d24s2 3d34s2 3d54s1 3d54s2 3d64s2 3d74s2 3d84s2 3d104s1 3d104s2
Outer electron configurations beyond [Ar] for the ground state of the simple atom (ion configuration)

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.

PLEASE note: The electrode potentials (EØ) for nickel chemistry in the text sometimes vary from the chart above - apologies, but data sources for nickel chemistry can vary! Any discrepancy shouldn't significantly affect any electrode potential calculation outcomes e.g feasibility (email if concerned?).

5. NICKEL(II) CHEMISTRY and complexes

  • 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 :C≡O

    • 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 :C≡N–).

      • [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

TOP OF PAGE

6. 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-

TOP OF PAGE

7. An example of the heterogeneous catalytic action of nickel metal - hydrogenation

  •  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)

    • Note the two transition state 'humps' for the catalysed reaction.

    • 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.

8. The vertical connection of nickel with the other d-block elements of Group 10 (IUPAC designation)

Modern IUPAC group numbers of 3-12 Outer electron structure of d-block elements which includes the transition metals

Nickel is the head element of Group 10 plus Palladium, Plutonium and Darmstadtium

Their outer electron configurations are nd8(n+1)s2 (n = 3 to 6) (except Pd 4d10. Pt 5d9s1)
[e- core] Gp 3 Group 4 Group 5 Group 6 Group 7 Group 8 Group 9 Group 10 Group 11 Group 12
P'd 4, 3d block [Ar] core 21Sc

3d14s2

 22Ti

3d24s2

 23V

3d34s2

 24Cr

3d54s1

 25Mn

3d54s2

 26Fe

3d64s2

 27Co

3d74s2

 28Ni

3d84s2

 29Cu

3d104s1

 30Zn

3d104s2
P'd 5, 4d block (Kr] core 39Y

4d15s2

 40Zr

4d25s2

 41Nb

4d45s1

 42Mo

4d55s1

 43Tc

4d55s2

 44Ru

4d75s1

 45Rh

4d85s1

 46Pd

4d10

 47Ag

4d105s1

 48Cd

4d105s2
P'd 6, 5d b'k  [Xe] core 57La

5d16s2

 72Hf

4f145d26s2

 73Ta

4f145d36s2

 74W

4f145d46s2

 75Re

4f145d56s2

 76Os

4f145d66s2

 77Ir

4f145d76s2

 78Pt

4f145d96s1

 79Au

4f145d106s1

 80Hg

4f145d106s2
P'd 7, 6d b'k [Rn] core 89Ac

6d17s2

 104Rf

5f146d27s2

 105Db

5f146d37s2

 106Sg

5f146d47s2

 107Bh

5f146d57s2

 108Hs

5f146d67s2

 109Mt

5f146d77s2

 110Ds

5f146d87s2

 111Rg

5f146d97s2

 112Cn

5f146d107s2

You should expect some similarities between the chemistry of nickel, palladium and platinum.

They have an outer electron configuration of 10 electrons - variable configuration

Learning objectives for the chemistry of the 3d block metal nickel 28Ni (a true transition element)

Know that nickel is a 3d block element and its position in the periodic table.

Nickel is the top-head element of group 10 (modern IUPAC convention).

Know that nickel is a 3d block element because it has one or more electrons in the 3d inner shell.

Know that nickel has relatively high melting point and boiling point, and a relatively high density.

Nickel is ferromagnetic i.e. a strongly magnetisable material that retains its magnetism without the need of an external magnetic field and so is used in alloys to make strong permanent magnet.

Know there are many important alloys that contain nickel including nichrome wire.

Nickel metal complies with the definition of a transition element, because it forms at least one ion with partially filled d sub–shell containing at least one electron

Know how to work out the electron configurations of nickel and its simple ions (equal to oxidation states).

Know that nickel does display compounds or ions in several oxidation states i.e. +2 and +3.

Be able to relate the oxidation states of nickel to their electron configurations.

Know that nickel can form complex ions, with the variety of ligands and colours characteristic of true transition metals.

e.g the hexaaquanickel(II) ion [Ni(H2O)6]2+(aq) and with ammonia to give the hexaamminenickel(II) ion  [Ni(NH3)6]2+(aq) in a ligand displacement reaction, so make sure can write the necessary balanced equations and draw the shapes of the octahedral complexes involved.

Know that nickel(II) salt solutions give a green? precipitate with alkalis like sodium hydroxide.

Know that nickel(II) ions form complexes with bidentate ligands such as 1,2-diaminoethane in process often called chelation.

Know that nickel and its compounds can display the catalytic properties of true transition metals e.g. hydrogenation of unsaturated fats is catalysed by a nickel or alloy of nickel.

WHAT NEXT?

 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.

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+ 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 inorganic chemistry revision notes for pre-university level students on 3d-block elements including the physical and chemical properties reactions equations and trends explained for the 3d-block of transition metals series Explaining the importance of chemistry of nickel in inorganic chemistry, What you need to know about chemistry of nickel for inorganic chemistry, Explaining the use of chemistry of nickel knowledge in inorganic chemistry, Examples of chemistry of nickel explained when studying inorganic chemistry, What is the significance of chemistry of nickel in inorganic chemistry, What is the use of chemistry of nickel in inorganic chemistry  Describing and explaining the theory of chemistry of nickel when studying inorganic chemistry, exam revision notes for chemistry of nickel in exams, online help for chemistry of nickel, revision notes for chemistry of nickel, what do I need to learn for chemistry of nickel in exams? revision summary for chemistry of nickel, help in teaching chemistry of nickel, learning notes for chemistry of nickel, help to pass the chemistry of nickel exam, how to prepare for examination questions on chemistry of nickel? Website content © Dr Phil Brown 2000+. All copyrights reserved on revision notes, images, quizzes, worksheets etc. Copying of website material is NOT permitted. Exam revision summaries & references to science course specifications are unofficial. Website content © Dr Phil Brown 2000+. All copyrights reserved on these organic chemistry exam revision notes on chemistry of nickel, these A level chemistry revision notes are suitable for use of pre-university students studying AQA advanced A level inorganic chemistry revision notes on chemistry of nickel, Edexcel advanced A level inorganic chemistry revision notes on chemistry of nickel, OCR advanced A level inorganic chemistry revision notes on chemistry of nickel, IB advanced A level inorganic chemistry revision notes on chemistry of nickel, WJEC (Eduqas) advanced A level inorganic chemistry revision notes on chemistry of nickel, CIE Cambridge advanced A level inorganic chemistry revision notes on chemistry of nickel, CCEA advanced A level inorganic chemistry revision notes on chemistry of nickel, and useful for US grade 11 grade 12 AP honors inorganic chemistry courses involving chemistry of nickel

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