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651.

Atomic number of `Mn , Fe CO and Ni ` are 25,26,27 and 28 respectively . Which of the following outer orbital octahedral complexes have same number of unpaired electrons ? `I. [MnCl_(6)]^(3-)" "II. [FeF_(6)]^(3-)` `III. [CoF_(6)]^(3-)" " IV. [Ni(NH_(3))_(6)]^(2+)`ltbrlt choose the correct code .A. `I and II `B. `II and IV `C. `I , III and IV `D. `I and III `

Answer» Correct Answer - D
`[MnCl_(6)]^(3-) and [CoF_(6)]^(3-)` have same number of unpaired electrons .
652.

`[Fe(H_2O)_6]^(3+)` is strongly paramagnetic whereas `[Fe(CN)_6]^(3-)` is weakly paramagnetic. Explain.A. If both Assertion and reason are true and reason is the correct explanation of assertionB. If both assertion and reason are true but reason is not the correct explanation of assertionC. If assertion is true but reason is falseD. if both assertion and reason are false

Answer» Correct Answer - A
653.

Predict the number of unpaired electrons in the square planar `[Pt(CN)_4]^(2-)` ion.

Answer» For square planar shape, the hybridisation is `dsp^(2)`. Hence theunpaired electrons in 5d orbital pair up to make one d orbitalempty for `dsp^(2)` hybridisation. Thus there is no unpaired electron
654.

The octahedral complex of a metal ion `M^(3+)` with four monodentate ligands `L_(1),L_(2),L_(3) and L_(4)` absorb wavelength in the region of red, green, yellow and blue, respectively. The increasing order of ligand strength of the four ligands is :A. `L_(4) lt L_(3) lt L_(2) lt L_(1)`B. `L_(1) lt L_(3) lt L_(2) lt L_(4)`C. `L_(3) lt L_(2) lt L_(4) lt L_(1)`D. `L_(1) lt L_(2) lt L_(4) lt L_(3)`

Answer» Correct Answer - B
655.

The octahedral complex of a metal ion `M^(3+)` with four monodentate ligands `L_(1),L_(2),L_(3)` and `L_(4)` absorb wavelengths in the region of red,green, yellow and bule, respectively The increasing order of ligand strengh of the four ligands isA. `L_(4) lt L_(3), L_(2) lt L_(1)`B. `L_(1) lt L_(3) lt L_(2) lt L_(4)`C. `L_(3) lt L_(2) lt L_(4) lt L_(1)`D. `L_(1) lt L_(2) lt L_(4) lt L_(3)`

Answer» Correct Answer - B
656.

STATEMENT-1: Tetrahedral complexes with chiral structure exhibit optical isomerism . and STATEMENT-2: They lack plane of symmetry .A. Statement-1 is True , Statement-2 is True , Statement-2 is a correct explanation for Statement-1B. Statement-1 is True , Statement-2 is True , Statement-2 is NOT a correct explanation for Statement-1C. Statement-1 is True , Statement-2 is FalseD. Statement-1 is False , Statement-2 is True

Answer» Correct Answer - A
657.

Consider the follwing complexes ion `P,Q` and `R` `P =[FeF_(6)]^(3-), Q=[V(H_(2)O)_(6)]^(2+)` and `R=[Fe(H_(2)O)_(6)]^(2+)` The correct order of the complex ions, according to their spin only magnetic moment values (inBM) is .A. `R lt Q lt P`B. `Q lt R lt P`C. `R lt P lt Q`D. `O lt P lt R`

Answer» Correct Answer - B
658.

Consider the follwing complexes ion `P,Q` and `R` `P =[FeF_(6)]^(3-), Q=[V(H_(2)O)_(6)]^(2+)` and `R=[Fe(H_(2)O)_(6)]^(2+)` The correct order of the complex ions, according to their spin only magnetic moment values (inBM) is .A. `R lt Q lt P`B. `Q lt P lt R`C. `Q lt R lt P`D. `R lt P lt Q`

Answer» Correct Answer - C
`P = [FeF_(6)]^(3-) implies Fe^(3+) (3d^(5)) implies 5` unpaired `bar e` s
`Q = [V(H_(2)O)_(6)]^(2+) implies V^(2+)(3d^(3)) implies 3` unpaired `bar e` s
`R = [Fe(H_(2)O)_(6)]^(2+) implies Fe^(2+) (3d^(6)) 4` unpaired `bar e` s
Since both `F^(-)` and `H_(2)O` are weak field ligands, the no. of unpaired electrons remains unchanged during the formation of complex ion. Thus option (3) is correct.
659.

An aqueous pink solution of cobalt (II) chloride changes to deep blue on addition of excess of `HCl`. This is because ....... .A. `[Co(H_(2)O_(6)]^(2+)` is transformed into `[CoCl_(6)]^(4-)`B. `[Co(H_(2)O)_(6)]^(2+)` is transformed into `[CoCl_(4)]^(2-)`C. tetrahedral complexes have smaller crystal field splitting than octahedral complexesD. Tetrahedral complexes have larger crystal field splitting than octahedral complex

Answer» Correct Answer - B::C
Aqueous pink solution of cobalt (II) chloride is due to electronic transition of electron from `t_(2g)` to `e_(g)` energy level of `[Co(H_(2)O)_(6)]^(2+)` complex. When excess of HCl is added to this solution
(i) `[Co(H_(2)O)_(6)]^(2+)` is transformed into `[CoCl_(4)]^(2-)`.
(ii) Tetrahedral complexes have smaler crystal field splitting than octahedral complexes because `Delta_(t)=4/9 Delta_(0)`
Hence , option (b) and (c) are correct choices.
660.

Geometrical shapes of the complex formed by the reaction of `Ni^(2+)` with `Cl^(Θ),CN^(Θ)` and `H_(2)O` are :A. octahedral, tetrahedral and square planarB. tetrahedral, sqare planar and octahedralC. square planar, tetrahedral and octahedralD. octahedral, square planar and octahedral

Answer» Correct Answer - B
661.

Addition of excess aqueous ammonia to a pink coloured aqueous solution of `MCl_(2).6H_(2)O(X)` and `NH_(4)Cl` gives an octahedral complex Y in the presence of air. In aqueous solution, complex Y behaves as 1:3 electrolyte. The reaction of X with excss HCl at room temperature results in the formation of a blue coloured complex Z. the calculated spin only magnetic moment of X and Z is 3.87 BM, whereas it is zero of complex Y. Among the following options, which statement(s) is (are) correct ?A. The hybridization of the central metal ion in Y is `d^(2)sp^(3)`B. Addition of silver nitrate of Y gives only tow equivalents of silver chlorideC. When X and Z in equilibrium at `0^(@)C`, the colour of the solution is pinkD. Z is a tetrahedral complex.

Answer» Correct Answer - A::C::D
662.

Assertion `[Ti (H_(2)O)_(6)] Cl_(4)` is colourless while `[Sc (H_(2)O)_(6)] Cl_(3)` is coloured. Reason `d-d` transition is not possible in `[Ti (H_(2)O)_(6)] Cl_(4)`A. Both assertion and reason are correct and reason is the correct explanation of the assertion.B. Both assertion and reason are correct but reason is not the correct explantionC. Assertion is correct but reason is incorrectD. Assertion is incorrect but reason is correct

Answer» Correct Answer - D
663.

Complexes expected to be coloured in solution is/areA. `K_(5) [CrF_(6)]`B. `[Co (NH_(3))_(6)] Cl_(3)`C. `K_(3) [FeCl_(6)]`D. `K_(3)[CoCl_(6)]`

Answer» Correct Answer - B::D
664.

The volume (in `mL`) of `0.1M Ag NO_(3)` required for complete precipitation of chloride ions present in `30 mL` of `0.01M` solution of `[Cr(H_(2)O)_(5)Cl]Cl_(2)`, as silver chloride is close to:

Answer» Correct Answer - 3
Complex of type `[Mabcd]^(n+-)` shows `3.GI` .
665.

Among the following complexes : `K_(3)[Fe(CN)_(6)],[Co(NH_(3))_(6)]Cl_(3)` , `Na_(3)[Co ( o x )_(3)],[Ni(H_(2)O)_(6)]Cl_(2)`, `K_(2)[Pt(CN)_(4)]` and `[Zn(H_(2)O)_(6)(NO_(3))_(2)]` The diamagnetic are .A. K,L,M,NB. K,N,O,PC. L,M,O,PD. L,M,N,O

Answer» Correct Answer - C
666.

Among the following complexes : `K_(3)[Fe(CN)_(6)],[Co(NH_(3))_(6)]Cl_(3)` , `Na_(3)[Co ( o x )_(3)],[Ni(H_(2)O)_(6)]Cl_(2)`, `K_(2)[Pt(CN)_(4)]` and `[Zn(H_(2)O)_(6)(NO_(3))_(2)]` The diamagnetic are .A. (a) K, L, M, NB. (b) L, M, O, PC. (c) K, M, O, PD. (d) L, M, N, O

Answer» Correct Answer - B
`[K]: K_3[Fe(CN)_6]:` `Fe^(3+)` has `3d^5` configuration, `CN^(-)` is strong field ligand and thus four electrons are paired leaving one unpaired electron with `d^2sp^3` hybridization and thus paramagnetic.
`[L]: [Co(NH_3)_6]Cl_3:Co^(3+)` has configuration, `NH_3` is strong field ligand thus all six electrons are paired with `d^2sp^3` hybridization and therefore diamagnetic.
`[M]: Na_3[Co(o x)_3]: Co^(3+)` has `3d^6` configuration, `C_2O_4^(2-)` is strong field ligand and thus all the six electrons are paired with `d^2sp^3` hybridisation and therefore diamagnetic.
`[N]: [Ni(H_2O)_6]Cl_2: Ni^(2+)` has `3d^8` configuration with two unpaired electrons. `H_2O` is weak field ligand and thus `sp^3d^2` hybridisation and paramagnetic.
`[O]: K_2[Pt(CN)_4]: Pt^2` has `3d^8` configuration, `CN^(-)` is strong field ligand and thus all the eight electrons are paired with `dsp^2` hybridisation and therefore diamagnetic.
`[P]: [Zn(H_2O)_6](NO_3)_2: Zn^(2+)` has `3d^(10)` configuration and thus all paired showing `sp^3d^2` hybridisation and so diamagnetic.
667.

Among the following , the coloured compound isA. `CuCl`B. `K_(3) [Cu (CN)_(4)]`C. `CuF_(2)`D. `[Cu (CH_(3) CN)_(4)] BF_(4)`

Answer» Correct Answer - C
668.

The spin only magnetic moment value ( in Bohr magneton units ) of `Cr(CO)_(6)` is :

Answer» Correct Answer - A
669.

The spin-only magnetic moment [in units of Bohr magneton, `(mu_(B)` of `Ni^(2+))` in aqueous solution would be (atomic number of `Ni=28)`A. 2.84B. 4.8C. 0D. 1.73

Answer» Correct Answer - A
670.

The spin only magnetic moment value of `Cr(CO)_(6)` isA. 2.84 B.MB. 4.90 B.M.C. 5.92 B.MD. 0 B.M.

Answer» Correct Answer - D
671.

Among the following complexes : `K_(3)[Fe(CN)_(6)],[Co(NH_(3))_(6)]Cl_(3)` , `Na_(3)[Co ( o x )_(3)],[Ni(H_(2)O)_(6)]Cl_(2)`, `K_(2)[Pt(CN)_(4)]` and `[Zn(H_(2)O)_(6)(NO_(3))_(2)]` The diamagnetic are .A. K, L, M, NB. K, M, O, PC. L, M, O, PD. L, M, N, O

Answer» Correct Answer - C
672.

The spin only magnetic moment value (in Bohr magnetion units) of `Cr(CO)_(6)` is

Answer» Correct Answer - A
673.

The complex showing a spin -magnetic momnet of `2.82 BM` is .A. `Ni(CO)_(4)`B. `[NiCI_(4)]^(2-)`C. `Ni(PPh_(3))_(4)`D. `[Ni(CN)_(4)]^(2-)`

Answer» Correct Answer - d
Refer to Table 7.15(H) .
674.

The complex showing a spin -magnetic momnet of `2.82 BM` is .A. `Ni (CO)_(4)`B. `[NiCl_(4)]^(2)`C. `Ni (PPh_(3))_(4)`D. `[Ni (CN)_(4)]^(2-)`

Answer» Correct Answer - B
675.

Dimethyl glyoxime forms a square planard complex with `Ni^(2+)`. This complex should beA. diamagneticB. paramagnetic having 1 unpaired electronC. paramagnetic having 2 unpaired electronsD. ferromagnetic .

Answer» Correct Answer - A
676.

Which one of the following is an inner orbital complex as well as diamagnetic in nature?A. (a) `[Cr(NH_3)_6]^(3+)`B. (b) `[Co(NH_3)_6]^(3+)`C. (c) `[Ni(NH_3)_6]^(2+)`D. (d) `[Zn(NH_3)_6]^(2+)`

Answer» Correct Answer - B
In `[Zn(NH_3)_6]^(3+)`, `Zn` exists as `Zn^(2+) ._(30)Zn: 3d^(10), 4s^2`
`Zn^(2+): 3d^(10)`. Thus, no unpaired electron but it is outer orbital complex.
In `[Co(NH_3)_6]^(3+)`, Co exists as `Co^(3+)`
`._(27)Co:3d^7, 4s^2`
`Co^(3+): 3d^(6)`, It is `d^2 sp^3` inner orbital complex with no unpaired `e^(-)` in `3d` due to forced pairing.
677.

Match the complexes in Column I with their properties listed in Column II A. `{:("A","B","C","D",),(4,2,3,1,):}`B. `{:("A","B","C","D",),(3,1,4,2,):}`C. `{:("A","B","C","D",),(2,1,3,4,):}`D. `{:("A","B","C","D",),(1,3,4,2,):}`

Answer» Correct Answer - A::B::C::D
678.

Which of the following statements is not true about the complex ion `[Pt(en)_2Cl_2]^(2+)`?A. It has two geometrical isomers - cis and transB. Both the cis and trans isomers display optical activity.C. Only the cis isomer displays optical acitivityD. Only the cis isomer has non-superimposable mirror image.

Answer» Correct Answer - B
679.

The magnetic moment of a complex `(A)` of Co was found to be `4.89BM` and the `EAN as 36` co alos forms complex `(B)` with magnetic moment `3.47BM` and `EAN` as37 and complex `(C )` with `EAN` as `36but` diamagnetic Which of the following statements is true regarding the above observation?A. The oxidation states of Co in (A),(B) and `(C )` are `+3,+2` and `+3` respectively .B. Complexes `(A)` and `(B)` have `sp^(3)d^(2)` hybridisation state while `(C )` has `dsp^(3)` hybrisation state .C. The spin multiplicities of Co in `(A),(B)` and `(C )` are 3,2 and 1,respectively .D. The oxidation states of `Co` in `(A),(B)` and `(C )` are `+6,+8` and `+1` respectively .

Answer» Correct Answer - A
680.

An aqueous solution of metal ion `MI` reacts separately with reagents `Q` and `R` in excess to give tetrahedral and square planar complexes, respectively An aqueous solution of another metal ion `M2` always forms tetrahedral complexs with theses reagents. Aqueous solution of `M2` on reaction with reagent `S` gives white precipitate which dissolves in excess of `S` The reactions are summarised in the scheme given below: `SCHEME` : what is M2 and S??A. `Zn^(2+)`, KCN, HCI and `K_(4)[Fe(CN)_(6)]`B. `Ni^(2+)`, HCI, KCN and KOHC. `Cd^(2+),KCN,HCl` and `Na_(2)HPO_(4)`D. `Co^(2+)`, HCI, KCN and `K_(2)CrO_(4)`

Answer» Correct Answer - B
`underset("Tetrahedral")([NiCl_(4)]^(2-))overset(HCl(Q))underset("excess")larr underset((M_(1)))(Ni^(2+))overset(KCN(R ))underset("excess")rarr underset("square planar")([Ni(CN)_(4)]^(2-))`
`underset("Tetrahedral")([ZnCl_(4)]^(2-))overset(HCl(Q))underset("excess")larrunderset(darr) underset((M_(2)))(Zn^(2+))overset(KCN(R ))underset("excess")rarr underset("Tetrahedral")([Zn(CN)_(4)]^(2-))`
`underset("white ppt.")(Zn(OH)_(2))overset(KOH)underset("excess")rarr[Zn(OH)_(4)]^(2-)`
681.

Which bond properties are consistent with one another?A. `{:(Bond "order",,Bond"length",,Vibrational frequency),(higher,,"shorter",,higher):}`B. `{:(Bond "order",,Bond"length",,Vibrational frequency),(lower,,"shorter",,lower):}`C. `{:(Bond "order",,Bond"length",,Vibrational frequency),(higher,,"longer",,lower):}`D. `{:(Bond "order",,Bond"length",,Vibrational frequency),(lower,,"longer",,higher):}`

Answer» Correct Answer - A
682.

Spin only magnetic moments of a `d^(8)` ion in octahedral square planar and tetrahedral complexes, respectively are .A. `2.8BM,0` and `2.8BM`B. `0,0` and `BM`C. `2.8,2.8` and `BM`D. None of these

Answer» Correct Answer - A
683.

The number of geometrical isomers for octahedral `[CoCl_(4)(NH_(3))_(2)]^(-)`, square planar `[AuBr_(2)Cl_(2)]^(-)` and `[PtCl_(2)(en)]` areA. 4,2B. 2,2C. 3,2D. 2,3

Answer» Correct Answer - B
684.

Which of the following square planar complexes will form two geometrical isomers?A. (a) `MA_4`B. (b) `MA_3B`C. (c) `MAB_3`D. (d) `MA_2B_2`

Answer» Correct Answer - D
`{:(cis-,,,,trans-),(,,,,):}`
685.

Which one of the following will be able to show geometrical isomerism if complexes are square planar? .A. `Ma_(4)`B. `Ma_(3)b`C. `Mabcd`D. `[M(A A)_(2)]`

Answer» Correct Answer - C
686.

Which kind of isomerism is exhibited by octahedral `[Co(NH_(3))_(4)Br_(2)]Cl` ?A. Geometrical and ionizationB. Geometrical and opticalC. Optical and ionizationD. Geometrical only

Answer» Correct Answer - A
687.

`Co^(2+)(aq.)+SCN^(-) (aq.) to "Complex"(X)` `Ni^(2+)(aq.) +"Dimethylglyoxime" overset(NH_(4)OH) to "Complex"(Y)` The coordination number of cobalt and nickel in complexes X and Y are four. The IUPAC name of the complexes (X) and (Y) are respectively :A. tetrathiocyanoato-S-cobalt(II) and bis(dimethylglyoximate) nickel (II).B. tetrathiocyanoato-S-cobaltate(II) and bis(dimethylglyoximato) nickel (II).C. tetrathiocyanoato-S-cobaltate(II) and bis(dimethylglyoximato) nickelate (II).D. tetrathiocyanoato-S-cobaltate(III) and bis(dimethylglyoximato) nickel (II).

Answer» Correct Answer - B
688.

`Co^(2+)(aq.)+SCN^(-) (aq.) to "Complex"(X)` `Ni^(2+)(aq.) +"Dimethylglyoxime" overset(NH_(4)OH) to "Complex"(Y)` The coordination number of cobalt and nickel in complexes X and Y are four. The geometry of complexes (X) and (Y) are respectively :A. tetrahedral and square planar.B. both tetrahedralC. square planar and tetrahedralD. both square planar.

Answer» Correct Answer - A
689.

Assertion: All square planar complexes can exhibit geometrical isomerism Reason: In square planar complexes .A. If both `(A)` and ` (R )` are correct and `(R )` is the correct explanation of `(A ) ` .B. If both `(A)` and ` (R )` are correct and `(R )` is the correct explanation of `(A ) ` .C. If`(A)` is correct, but `( R )` is incorrect .D. Both `(A)` and `(R ) ` are incorrect .

Answer» Correct (A) only `Ma_(2)b_(2)` and Mabcd type shows geometrical isomerism
Correct `(R )` Square planar complexes assume `dsp^(2)` -hybrid state .
690.

The spin magnetic moment of cobalt in the compound , `Hg[Co(SCN)_(4)]` is :A. `sqrt(3)`B. `sqrt(8)`C. `sqrt(12)`D. `sqrt(24)`

Answer» Correct Answer - C
691.

The geometries of `Ni(CO)_(4)` and `Ni(PPh_(3))_(2)Cl_(2)` are .A. both square planarB. tetrahedral and square plana, respectivelyC. both tetrahedralD. square planar and tetrahedral, respectively

Answer» Correct Answer - C
692.

Both `[Ni(CO)_(4)] and [Ni(CN)_(4)]^(2-)` are diamagnetic. The hybridisation of nickel in these complexes, respectively are :A. `sp^(3),sp^(3)`B. `sp^(3),dsp^(3)`C. `dsp^(2),sp^(3)`D. `dsp^(2),sp^(2)`

Answer» Correct Answer - B
693.

Which one of the following high-spin complexes has the largest CFSE (Crystal Field stabilization energy ) ?A. `[Mn(H_(2)O)_(6)]^(2+)`B. `[Cr(H_(2)O)_(6)]^(2+)`C. `[Mn(H_(2)O)_(6)]^(3+)`D. `[Cr(H_(2)O)_(6)]^(3-)`

Answer» Correct Answer - D
`[Mn(H_(2)O)_(6)]^(2+)=3xx(-0.4)+2xx(0.6)=0," " [Cr(H_(2)O)_(6)]^(2+)=3xx(-0.4)+1xx(0.6)=0.6Delta_(0)`
`[Mn(H_(2)O)_(6)]^(3+)=3xx(-0.4)+1xx(0.6)=0.6Delta_(0):" " [Cr(H_(2)O)_(6)]^(=3)=3xx(-0.4)+0xx(0.6)=1.2Delta_(0)`
694.

In which of the following complexes the nickel metal is in highest oxidation state:A. `Ni(CO)_(4)`B. `K_(2)NiF_(5)`C. `[Ni(NH_(3))_(5)](BF_(4))_(2)`D. `K_(4)[Ni(CN)_(6)]`

Answer» Correct Answer - B
Let x be the oxidation state of nickel then,
(1) `Ni(CO)_(4),x+4(0)=0 or x=0," " (2)[NiF_(6)]^(2-),x+6(-1)=-2 or x=+4,`
`(3) [Ni(NH_(3))_(6)]^(2+),x+4(0)=+2 or x=+2," " (4)[Ni(CN)_(6)]^(4-),x+6(-1)=-4 or x=+2`.
695.

The compound in which nickel has the lower oxidation states is :A. `Ni(CO)_(4)`B. `(CH_(3)COO)_(2)Ni`C. `NiO`D. `NiCl_(2)(PPh_(3))_(2)`

Answer» Correct Answer - A
696.

The `IUPA` name of the complex having formula `[CO)_(3)Fe(CO)_(3)Fe(CO)_(3)]` is .A. Monocarbonylferrate(0)B. Tricarbonyliron`(0)-mu`-tricarbonyliron(0)C. Tri`-mu` carbonylbis-{tricarbonyliron(0)}D. Hexacarbony1 `-mu- tricarbonyliron(III)

Answer» Correct Answer - C
697.

Write the structural formula corresponding to each of the following IUPAC names : (a) potassium tetracyanidozincate (II) (b) tetracarbonyl nickel (0) ( c) potassium tetracyanonickelate (0) (d) potassium tris (oxalato) aluminate (III)

Answer» Correct Answer - `(a) K_(2)[Zn^(II)(CN)_(4)] (b) [Ni^(0)(CO)_(4)] (c ) K_(4)[Ni^(0)(CN)_(4)] (d) K_(3)[Al^(III)(C_(2)O_(4))_(3)]`
Refer IUPAC rule.
698.

STATEMENT-1: `[M(en)Cl_(2)Br_(2)]` is optically active complex . STATEMENT-2: en is a bidentate ligand . STATEMENT-3: In `K[Cu(CN)_(2)]` , co-ordination number of Cu is 3 .A. TFTB. TTTC. TFFD. FTT

Answer» Correct Answer - 4
699.

In octaamine `-mu`-dihydroxodiiron(III)sulphate the number of bridging ligands isA. 2B. 1C. 3D. None

Answer» Correct Answer - A
700.

Write the IUPAC name of the following : (a) `[Cr(acac)_(3)]` (b) `[V(H_(2)O)_(6)]Cl_(3)` ( c) `(NH_(4))_(3)[Co(C_(2)O_(4))_(3)]` (d) `K_(2)[CrO_(4)]`

Answer» Correct Answer - (a) tris (acetylacetonato) chromium (III)
(b) hexaaquavanadium (III) chloride
( c) ammonium tris ( oxalato) cobaltate (III) or ammonium trioxalatocobaltate (III)
(d) potassium tetraoxidochromate (VI)
Refer IUPAC nomenclature rule.