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Inductomeric effect is the temporary effect which enhances the inductive effect and it accounts only in the presence of an attacking reagent.             Example, In methyl chloride the - I effect of \[Cl\] group is further increased temporarily by the approach of hydroxyl ion.

(1) When a \[H-C\] bond is attached to an unsaturated system such as double bond or a benzene ring, the sigma \[(\sigma )\] electrons of the \[H-C\] bond interact or enter into conjugation with the unsaturated system. The interactions between the electrons of \[\pi \] systems (multiple bonds) and the adjacent \[\sigma \] bonds (single \[H-C\] bonds) of the substituent groups in organic compounds is called hyperconjugation. The concept of hyperconjugation was developed by Baker and Nathan and is also known as Baker and Nathan effect. In fact hyperconjugation effect is similar to resonance effect. Since there is no bond between the \[\alpha \]-carbon atom and one of the hydrogen atoms, the hyperconjugation is also called no-bond resonance. (2) Structural requirements for hyperconjugation (i) Compound should have at least one \[s{{p}^{2}}\]-hybrid carbon of either alkene alkyl carbocation or alkyl free radical. (ii) \[\alpha \]-carbon with respect to \[s{{p}^{2}}\]hybrid carbon should have at least one hydrogen. If both these conditions are fulfilled then hyperconjugation will take place in the molecule. (iii) Hyperconjugation is of three types (iv) Resonating structures due to hyperconjugation may be written involving “no bond” between the alpha carbon and hydrogen atoms. \[H-\underset{H}{\mathop{\underset{|}{\mathop{\overset{H}{\mathop{\overset{|}{\mathop{C}}\,}}\,}}\,}}\,-CH=C{{H}_{2}}\underset{{}}{\longleftrightarrow}H-\underset{H}{\mathop{\underset{|}{\mathop{\overset{\overset{\oplus }{\mathop{H}}\,}{\mathop{\overset{{}}{\mathop{C}}\,}}\,}}\,}}\,=CH-\overset{}{\mathop{C}}\,{{H}_{2}}\underset{{}}{\longleftrightarrow}\] \[\overset{\oplus}{\mathop{H}}\,\underset{H}{\mathop{\underset{|}{\mathop{\overset{H}{\mathop{\overset{|}{\mathop{C}}\,}}\,}}\,}}\,=CH-\overset{}{\mathop{C}}\,{{H}_{2}}\underset{{}}{\longleftrightarrow}H-\underset{\underset{\oplus}{\mathop{H}}\,}{\mathop{\underset{{}}{\mathop{\overset{H}{\mathop{\overset{|}{\mathop{C}}\,}}\,}}\,}}\,=CH-\overset{}{\mathop{C}}\,{{H}_{2}}\] (v) Number of resonating structures due to the hyperconjugation = Number of \[\alpha \]-hydrogens + 1. Applications of hyperconjugation (1) Stability of alkenes : Hyperconjugation explains the stability of certain alkenes over other alkenes. Stability of alkenes \[\propto \]Number of alpha hydrogens \[\propto \]Number of resonating structures \[\xrightarrow[\text{Stability in decreasing order}]{C{{H}_{3}}-CH=C{{H}_{2}}>C{{H}_{3}}-C{{H}_{2}}-CH=C{{H}_{2}}>C{{H}_{3}}-\underset{C{{H}_{3}}}{\mathop{\underset{|\,\,\,\,\,\,\,\,}{\mathop{CH-}}\,}}\,CH=C{{H}_{2}}}\] (2) Carbon-carbon double bond length in alkenes : As we know that the more is the number of resonating structures, the more will be single bond character in carbon-carbon double bond. (3) Stability of alkyl carbocations : Stability of alkyl carbocations µ number of resonating structures µ number of alpha hydrogens. (4) Stability of alkyl free radicals : Stability of alkyl free radicals can be explained by hyperconjugation. Stability depends on the number of resonating structures. (5) Electron releasing (or donating) power of R in alkyl benzene : \[C{{H}_{3}}-\](or alkyl group) is \[+R\] group, ortho-para directing group and activating group for electrophilic aromatic substitution reaction because of the hyperconjugation. The electron donating power of alkyl group will depends on the number of resonating structures, this depends on the number of hydrogens present on \[\alpha -\]carbon. The electron releasing power of some groups are as follows, Electron donating power in decreasing order due to the hyperconjugation.            (6) Heat of hydrogenation : Hyperconjugation decreases the heat of hydrogenation.             (7) Dipole moment : Since hyperconjugation causes the development of charges, it also affects the dipole moment in the molecule.             The increase in dipole moment, when hydrogen of formaldehyde \[(\mu =2.27D)\] is replaced by methyl group, i.e., acetaldehyde \[(\mu =2.72D)\] can be referred to hyperconjugation, which leads to development of charges. (8) Orienting influence of alkyl group in \[o,\,p\]-positions and of \[-CC{{l}_{3}}\] group in \[m\]-position : Ortho-para more...

(1) The effect in which \[\pi \] electrons are transferred from a multiple bond to an atom, or from a multiple bond to a single covalent bond or lone pair (s) of electrons from an atom to the adjacent single covalent bond is called mesomeric effect or simply as M-effect. In case of the compound with conjugated system of double bonds, the mesomeric effect is transmitted through whole of the conjugated system and thus the effect may better be known as conjugative effect. (2) Groups which have the capacity to increase the electron density of the rest of the molecule are said to have \[+M\] effect. Such groups possess lone pairs of electrons. Groups which decrease the electron density of the rest of the molecule by withdrawing electron pairs are said to have \[-M\] effect, e.g., (a) The groups which donate electrons to the double bond or to a conjugated system are said to have \[+M\] effect or \[+R\] effect. \[+M\] effect groups : \[-Cl,\,-Br,\,-I,\,-\overset{.\,\,.}{\mathop{N}}\,{{H}_{2}},\,-N{{R}_{2}},-OH,-OR,-SH,-OC{{H}_{3}},-\overset{.\,\,.}{\mathop{\underset{.\,\,.}{\mathop{S}}\,}}\,R\] (b) The groups which withdraw electrons from the double bond or from a conjugated system towards itself due to resonance are said to have \[-M\] effect or \[-R\] effect. \[-M\] effect groups : \[-N{{O}_{2}},-C\equiv N,\,-\overset{O}{\mathop{\overset{|\,|}{\mathop{C}}\,}}\,-,-CHO,-COOH,-S{{O}_{3}}H\] (3) The inductive and mesomeric effects, when present together, may act in the same direction or oppose each other. The mesomeric effect is more powerful than the former. For example, in vinyl chloride due to \[-I\]  effect the chlorine atom should develop a negative charge but on account of mesomeric effect it has positive charge. Application of mesomeric effect : It explains, (1) Low reactivity of aryl and vinyl halides, (2) The acidic nature of carboxylic acids, (3) Basic character comparison of ethylamine and aniline, (4) The stability of some free radicals, carbocations and carbanions. Difference between Resonance and Mesomerism : Although both resonance and mesomerism represent the same phenomenon, they differ in the following respect : Resonance involves all types of electron displacements while mesomerism is noticeable only in those cases where a multiple bond is in conjugation with a multiple bond or lone pair of electron. Example :  (i)  (ii)   Both (i) and (ii) are the examples of mesomerism and resonance effect. Let us consider the following example. Such an electron displacement is the example of resonance only (not the mesomerism).

(1) When an electron withdrawing (X) or electron-releasing (Y) group is attached to a carbon chain, polarity is induced on the carbon atom and on the substituent attached to it. This permanent polarity is due to displacement of shared electron of a covalent bond towards a more electronegative atom. This is called inductive effect or simply as I - effect.             \[C-C-C-C\] Non polar \[{{C}^{\delta \delta \delta {{\delta }^{+}}}}\xrightarrow{{}}-{{C}^{\delta \delta {{\delta }^{+}}}}\xrightarrow{{}}-{{C}^{\delta {{\delta }^{+}}}}\xrightarrow{{}}-{{C}^{{{\delta }^{+}}}}\xrightarrow{{}}-{{X}^{{{\delta }^{-}}}}\] \[{{C}^{\delta \delta \delta {{\delta }^{-}}}}-\xleftarrow{{}}\,\,{{C}^{\delta \delta {{\delta }^{-}}}}-\xleftarrow{{}}\ {{C}^{\delta {{\delta }^{-}}}}-\xleftarrow{{}}\,{{C}^{{{\delta }^{-}}}}-\xleftarrow{{}}\,\,{{Y}^{{{\delta }^{+}}}}\] (2) Carbon-hydrogen bond is taken as a standard of inductive effect. Zero effect is assumed for this bond. Atoms or groups which have a greater electron withdrawing capacity than hydrogen are said to have–I effect whereas atoms or groups which have a greater electron releasing power are said to have +I effect. \[\xrightarrow[I\text{ }power\text{ }of\text{ }groups\text{ }in\text{ }decreasing\text{ }order\text{ }with\text{ }respect\text{ }to\text{ }the\text{ }referenceH]{CON{{H}_{2}}\,\,>\,\,F\,\,>\,\,Cl\,\,>Br\,\,>\,\,I\,\,>\,\,OH\,\,\,>\,\,\,OR\,\,\,>\,\,N{{H}_{2}}\,\,>\,\,{{C}_{6}}{{H}_{5}}\,\,>H}\] \[\xrightarrow[+\text{ }I\text{ }power\text{ }in\text{ }decreasing\text{ }order\text{ }with\text{ }respect\text{ }to\text{ }the\text{ }referenceH]{ter.alkyl\text{ }>sec.alkyl\text{ }>pri.alkyl\text{ }>}\]  \[\xrightarrow[\text{+I power in decreasing order in same type of alkyl groups}]{C{{H}_{3}}-C{{H}_{2}}-C{{H}_{2}}-C{{H}_{2}}->C{{H}_{3}}-C{{H}_{2}}-C{{H}_{2}}->C{{H}_{3}}-C{{H}_{2}}-}\] (3) Applications of Inductive effect (i) Magnitude of positive and negative charges : Magnitude  of +ve  charge  on cations  and magnitude of –ve charge on anions can be compared by \[+I\] or \[–I\]  groups present in it. Magnitude of \[+ve\] charge \[\propto \frac{1}{+\text{I power of the group}}\propto -I\] power of the group. Magnitude of \[-ve\] charge \[\propto \frac{1}{-\text{I power of the group}}\propto +I\] power of the group. (ii) Reactivity of alkyl halide : \[+I\] effect of methyl group enhances \[–I\] effect of the halogen atom by repelling the electron towards tertiary carbon atom. \[{{H}_{2}}C\to \underset{\begin{smallmatrix}  \uparrow  \\  C{{H}_{3}} \end{smallmatrix}}{\overset{\begin{smallmatrix}  C{{H}_{3}} \\  \downarrow  \end{smallmatrix}}{\mathop{C}}}\,\to X>{{H}_{3}}C\to \underset{{}}{\overset{\begin{smallmatrix}  C{{H}_{3}} \\  \downarrow  \end{smallmatrix}}{\mathop{CH}}}\,\to X\] \[>C{{H}_{3}}\to C{{H}_{2}}\to X>C{{H}_{3}}\to X\] Tertiary    >    Secondary   >   Primary  >  Methyl (iii) Relative strength of the acids : (a) Any group or atom showing \[+I\] effect decreases the acid strength as it increases the negative charge on the carboxylate ion which holds the hydrogen firmly. Alkyl groups have \[+I\] effect. Thus, acidic nature is, \[\xrightarrow[\text{+ I effect increases, so acid strength decreases}]{HCOOH\,\,>\,\,C{{H}_{3}}COOH\,\,>\,\,{{C}_{2}}{{H}_{5}}COOH\,\,>\,\,{{C}_{3}}{{H}_{7}}COOH\,\,>\,\,{{C}_{4}}{{H}_{9}}COOH}\]   Formic acid, having no alkyl group, is the most acidic among these acids. (b) The group or atom having \[-I\] effect increases the acid strength as it decreases the negative charge on the carboxylate ion. Greater is the number of such atoms or groups (having \[-I\]effect), greater is the acid strength. Thus, acidic nature is,   \[\xleftarrow[\left( \text{ Inductive effect increases, so acid strength increases} \right)]{\underset{\begin{smallmatrix}\text{Trichloro} \\ \text{acetic acid } \end{smallmatrix}}{\mathop{CC{{l}_{3}}COOH}}\,>\underset{\begin{smallmatrix} \text{Dichloro} \\ \text{acetic acid}\end{smallmatrix}}{\mathop{CHC{{l}_{2}}COOH}}\,>\underset{\begin{smallmatrix} \text{Monochloro} \\ \text{acetic acid} \end{smallmatrix}}{\mathop{C{{H}_{2}}ClCOOH}}\,>\underset{\text{Acetic acid}}{\mathop{C{{H}_{3}}COOH}}\,}\]   (c) Strength of aliphatic carboxylic acids and benzoic acid \[\underset{\begin{smallmatrix} \uparrow  \\ +I\,\text{group}\end{smallmatrix}}{\mathop{R}}\,\to COOH\,\,\,\,\,\,\,\underset{\begin{smallmatrix} \uparrow  \\ -I\,\text{group}\end{smallmatrix}}{\mathop{{{C}_{6}}{{H}_{6}}}}\,\leftarrow COOH\]   Hence benzoic acid is stronger acid than aliphatic carboxylic acids but exception is formic acid. Thus, \[\frac{HCOOH\,\,\,>\,\,\,\,\,{{C}_{6}}{{H}_{5}}COOH\,\,>\,\,RCOOH}{\text{Acid strength in decreasing order}}\to \]

• Decreasing order of acids :

\[N{{O}_{2}}C{{H}_{2}}COOH>FC{{H}_{2}}COOH>ClC{{H}_{2}}COOH>BrC{{H}_{2}}COOH\]. \[{{F}_{3}}C-COOH>C{{l}_{3}}C-COOH>B{{r}_{3}}C-COOH>{{I}_{3}}C-COOH\].   \[\underset{\begin{smallmatrix}Methyl \\alcohol\end{smallmatrix}}{\mathop{C{{H}_{3}}OH}}\,>\underset{\begin{smallmatrix}Ethyl \\Alcohol\end{smallmatrix}}{\mathop{C{{H}_{3}}C{{H}_{2}}OH}}\,>\underset{\begin{smallmatrix}Iso-propyl \\alcohol\end{smallmatrix}}{\mathop{{{(C{{H}_{3}})}_{2}}CHOH}}\,>\underset{\begin{smallmatrix}Tert-butyl \\alcohol\end{smallmatrix}}{\mathop{{{(C{{H}_{3}})}_{3}}COH}}\,\].    As compared to water, phenol is more acidic (\[-I\]effect) but methyl alcohol is less more...

It is observed that most of the attacking reagents always possess either a positive or a negative charge, therefore for a reaction to take place on the covalent bond the latter must possess oppositely charged centres. This is made possible by displacement (partial or complete) of the bonding electrons. The electronic displacement in turn may be due to certain effects, some of which are permanent and others are temporary. The former effects are permanently operating in the molecule and are known as polarisation effects, while the latter are brought into play by the attacking reagent and as soon as the attacking reagent is removed, the electronic displacement disappears; such effects are known as the polarisability effects.

On account of the presence of bulkier groups at the reaction centre, they cause mechanical interference and with the result the attacking reagent finds it difficult to reach the reaction site and thus slows down the reaction. This phenomenon is called steric hinderance or steric effect.             (1) Tertiary alkyl halides having bulky groups form tertiary carbocation readily when hydrolysed because of the presence of the three bulky groups on the carbon having halogen. (2) Primary alkyl halide having quaternary \[\beta \]-carbon does not form transition state because of the steric strain around \[\alpha \]-carbon by the \[\beta \]-carbon. To release the strain it converts into carbocation. (3)  Steric strain inhibits the resonance. This phenomenon is known as steric inhibitions of resonance.  

(1) The process of mixing atomic orbitals to form a set of new equivalent orbitals is termed as hybridisation. There are three types of hybridisation, (i) \[s{{p}^{3}}\] hybridisation (involved in saturated organic compounds containing only single covalent bonds), (ii) \[s{{p}^{2}}\] hybridisation (involved in organic compounds having carbon atoms linked by double bonds) and (iii) \[sp\] hybridisation (involved in organic compounds having carbon atoms linked by a triple bonds).   

Type of hybridisation	\[s{{p}^{3}}\]	\[s{{p}^{2}}\]	\[sp\]
Number of orbitals used	\[1s\] and \[3p\]	\[1s\] and  \[2p\]	\[1s\] and \[1p\]
Number of unused p-orbitals	Nil	One	Two
Bond	Four \[-\sigma \]	Three \[-\sigma \] One \[-\pi \]	Two \[-\sigma \] Two\[-\pi \]
more... Catgeory: JEE Main & Advanced Bonding in co-ordination compounds (Werner's Coordination theory) Werner was able to explain the bonding in complex. Primary valency (Pv) : This is non- directional and ionizable. In fact it is the positive charge on the metal ion. Secondary valency  (Sv) : This is directional and non- ionizable. It is equal to the number of ligand atoms co-ordinated to the metal (co-ordination number). Example :   \[[Co\,{{(N{{H}_{3}})}_{6}}]C{{l}_{3}}\] or \[Co{{(N{{H}_{3}})}_{6}}{{]}^{3+}}\,3C{{l}^{-}}\] \[Pv\to 3C{{l}^{-}}\,[3]\] Sv \[\to 6N{{H}_{3}}(6)\] \[[Co{{(N{{H}_{3}})}_{5}}Cl]C{{l}_{2}}\] or \[{{[Co{{(N{{H}_{3}})}_{5}}Cl]}^{2+}}2C{{l}^{-}}\] \[Pv\to 2C{{l}^{-}}(2)\] Sv \[\to 5N{{H}_{3}}+1C{{l}^{-}}(6)\] \[[Co{{(N{{H}_{3}})}_{4}}C{{l}_{2}}]\,Cl\] or \[{{[Co{{(N{{H}_{3}})}_{4}}C{{l}_{2}}]}^{+}}\,C{{l}^{-}}\] \[Pv\to C{{l}^{-}}(1)\] Sv \[\to 4N{{H}_{3}}+2C{{l}^{-}}(6)\]   Nature of the complex can be understood by treating the above complexes with excess of \[AgN{{O}_{3}}.\] \[CoC{{l}_{3}}.\,6N{{H}_{3}}\to 3AgCl,\,\,[Co{{(N{{H}_{3}})}_{6}}C{{l}_{3}}\](three chloride ion) \[CoC{{l}_{3}}.\,5N{{H}_{3}}\to 2AgCl,\,\,[Co{{(N{{H}_{3}})}_{5}}C{{l}_{2}}\](two chloride ion) \[CoC{{l}_{3}}.\,4N{{H}_{3}}\to 1AgCl,\,\,[Co{{(N{{H}_{3}})}_{4}}C{{l}_{2}}\] (one chloride ion) \[CoC{{l}_{3}}.\,3N{{H}_{3}}\to no\,AgCl,\,\,[Co{{(N{{H}_{3}})}_{3}}C{{l}_{3}}\](no  chloride ion) The nature of bonding between central metal atom and ligands in the coordination sphere has been explained by the three well-known theories. These are : (1) Valence Bond theory of coordination compounds (i) The suitable number of atomic orbitals of central metal ion (s, p, d) hybridise to provide empty hybrid orbitals. (ii) These hybrid orbitals accept lone pair of electrons from the ligands and are directed towards the ligand positions according to the geometry of the complex. (iii) When inner d-orbitals i.e. \[(n-1)d\] orbitals are used in hybridization, the complex is called – inner orbital or spin or hyperligated complex. (iv) A substance which do not contain any unpaired electron is not attracted by 2 magnet. It is said to be diamagnetic. On the other hand, a substance which contains one or more unpaired electrons in the electrons in the d-orbitals, is attracted by a magnetic field [exception \[{{O}_{2}}\] and NO]. It is said to be paramagnetic. Paramagnetism can be calculated by the expression, \[{{\mu }_{s}}=\sqrt{n(n+2),}\] where \[\mu =\] magnetic moment. s= spin only value and n= number of unpaired electrons. Hence, if \[n=1,\,{{\mu }_{s}}=\sqrt{1(1+2)}=1.73\,B.M.\], if \[n=3,\,{{\mu }_{s}}\] \[=\sqrt{3(3+2)}=3.87\,B.M.\]and so on On the basis of value of magnetic moment, we can predict the number of unpaired electrons present in the complex. If we know the number of unpaired electrons in the metal complex, then it is possible to predict the geometry of the complex species. (v) There are two types of ligands namely strong field and weak field ligands. A strong field ligand is capable of forcing the electrons of the metal atom/ion to pair up (if required). Pairing is done only to the extent which is required to cause the hybridization possible for that co-ordination number. A weak field ligand is incapable of making the electrons of the metal atom/ ion to pair up. Strong field ligands : \[C{{N}^{-}},CO,\,en,\,N{{H}_{3}},{{H}_{2}}O,\,N{{O}^{-}},Py\]. Weak field ligands more... Catgeory: JEE Main & Advanced Isomerism In Co-ordination Compounds Compounds having the same molecular formula but different structures or spatial arrangements are called isomers and the phenomenon is referred as isomerism.               (1) Structural isomerism : Here the isomers have different arrangement of ligands around the central metal atom. It is of the following types :  (i) Ionisation isomerism : The co-ordination compound having the same composition or molecular  formula but gives different ions in solution are called ionization isomers.  There is exchange of anions between the co-ordination sphere and ionization sphere.    Example : \[[Co\,Br\,{{(N{{H}_{3}})}_{5}}]\,S{{O}_{4}}\]   \[[Co\,S{{O}_{4}}{{(N{{H}_{3}})}_{5}}]\,\,Br\] Pentaaminebromo cobalt (III) Sulphate Pentaaminesulphato cobalt (III) bromide \[SO_{4}^{2-}\]present in ionisation sphere \[B{{r}^{-}}\] present in ionization sphere Gives white precipitate with \[BaC{{l}_{2}}\] Gives light  yellow precipitate with  \[AgN{{O}_{3}}\] (ii) Co-ordination isomerism : In this case compound is made up of cation and anion and the isomerism arises due to interchange of ligands between complex cation and complex anion. Example : \[[Co{{(N{{H}_{3}})}_{6}}]\,\,[Cr\,{{(CN)}_{6}}]\] \[[Cr\,{{(N{{H}_{3}})}_{6}}]\,[Co{{(CN)}_{6}}]\] hexaamine cobalt (III) hexacyano chromate (III)  hexaamine chromium (III) hexacyanocobalt (III) complex cation contains \[\to \]\[N{{H}_{3}}\] ligand (with cobalt)               complex anion contains  \[\to \]\[N{{H}_{3}}\] ligand (with chromium) complex anion contains \[\to \]\[C{{N}^{-}}\]ligand (with chromium)    complex anion contains \[\to \]\[C{{N}^{-}}\] ligand (with cobalt)  (iii) Linkage isomerism : In this case isomers differ in the mode of attachment of ligand to central metal ion and the phenomenon is called linkage isomerism.  Example : \[[Co\,ONO\,{{(N{{H}_{3}})}_{5}}]C{{l}_{2}}\]; \[[Co\,N{{O}_{2}}\,{{(N{{H}_{3}})}_{5}}]C{{l}_{2}}\] Pentaamminenitritocobalt (III)             Pentaaminenitrocobalt (III) chloride \[:O-N{{O}^{-}}\] oxygen atom donates lone pair of electrons (nitrito) \[NO_{2}^{-}\] nitrogen atom donates lone pair of electrons (nitro)  (iv) Hydrate isomerism : Hydrate isomers have the same composition but differ in the number of water molecules present as ligands and the phenomenon is called hydrate isomerism. Examples : (a) \[[Cr\,{{({{H}_{2}}O)}_{6}}]\,C{{l}_{3}}\] hexaaquachromium (III) chloride (violet) (b)\[[Cr\,{{({{H}_{2}}O)}_{5}}\,Cl\,]\,C{{l}_{2}}.\,{{H}_{2}}O\] pentaaquachlorochromium (III) chloride monohydrate (blue green) (c) \[[Cr{{({{H}_{2}}O)}_{4}}Cl]C{{l}_{2}}.2{{H}_{2}}O\] tetraaquadichloro chromium (III) chloride dihydrate (green) (2) Stereo isomerism or space isomerism : Here the isomers differ only in the spatial arrangement of atoms of groups about the central metal atom. It is of two types : (i) Geometrical or Cis-trans isomerism : This isomerism arises due to the difference in geometrical arrangement of the ligands around the central atom. When identical ligands occupy positions near to each other called cis-isomer. When identical ligands occupy positions opposite to each other called trans –isomer. It is very common in disubstituted complexes with co-ordination number of 4 and 6.  Complexes of more... Catgeory: JEE Main & Advanced Iupac Nomenclature Of Complex Compounds In order to name complex compounds certain rules have been framed by IUPAC. These are as follows :             (1) The positive part of a coordination compound is named first and is followed by the name of negative part.             (2) The ligands are named first followed by the central metal. The prefixes di-, tri-, tetra-, etc., are used to indicate the number of each kind of ligand present. The prefixes bis (two ligands), tris (three ligands),  etc., are used when the ligands includes a number  e.g., dipyridyl, bis (ethylenediamine).             (3) In polynuclear complexes, the bridging group is indicated in the formula of the complex by separating it from the rest of the complex by hyphens. In polynuclear complexes (a complex with two or more metal atoms), bridging ligand (which links two metal atoms) is denoted by the prefix \[\mu \] before its name.             (4) Naming of ligands : The different types of ligands i.e. neutral, negative or positive are named differently in a complex compound.             When a complex species has negative charge, the name of the central metal ends in -  ate. For some elements, the ion name is based on the Latin name of the metal (for example, argentate for silver). Some such latin names used (with the suffix - ate) are given below : Fe Ferrate Cu Cuperate Ag Argentate Au Aurate Sn more... 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