Inorganic Chemistry

GATE Chemistry (CY) — Organometallic Compounds previous year questions

27 questions · 2005 · all with verified answer · last checked 2026-11-06

Q1 · 2005-2021 · 2 marks

The value of \mathrm{M}-\mathrm{C} stretching frequencies of (i) \left[\mathrm{V}(\mathrm{CO})_{6}\right]^{-}, (ii) \left[\mathrm{Cr}(\mathrm{CO})_{6}\right] and (iii) \left[\mathrm{Mn}(\mathrm{CO})_{6}\right]^{+}follow ing the trend

(a) (ii) > (i) > (iii)
(b) (ii) > (iii) > (i)
(c) (i) > (ii) > (iii)
(d) (iii) > (ii) > (i)

Show answer

Answer: (c)

Report an error in ABC26IN0487

Q2 · 2005-2021 · 2 marks

The CORRECT order of the CO stretching vibrational frequency is

(a) \left[\mathrm{Ti}(\mathrm{CO})_{6}\right]^{2-}>\left[\mathrm{V}(\mathrm{CO})_{6}\right]^{-}>\mathrm{CO}>\left[\mathrm{Cr}(\mathrm{CO})_{6}\right]
(b) \left[\mathrm{Cr}(\mathrm{CO})_{6}\right]>\mathrm{CO}>\left[\mathrm{V}(\mathrm{CO})_{6}\right]^{-}>\left[\mathrm{Ti}(\mathrm{CO})_{6}\right]^{2-}
(c) \mathrm{CO}>\left[\mathrm{V}(\mathrm{CO})_{6}\right]^{-}>\left[\mathrm{Ti}(\mathrm{CO})_{6}\right]^{2-}>\left[\mathrm{Cr}(\mathrm{CO})_{6}\right]
(d) \mathrm{CO}>\left[\mathrm{Cr}(\mathrm{CO})_{6}\right]>\left[\mathrm{V}(\mathrm{CO})_{6}\right]^{-}>\left[\mathrm{Ti}(\mathrm{CO})_{6}\right]^{2-}

Show answer

Answer: (d)

Report an error in ABC26IN0491

Q3 · 2005-2021 · 2 marks

\quad \mathrm{W}(\mathrm{CO})_{6} reacts with MeLi to give an intermediate which upon treatment with \mathrm{CH}_{2} \mathrm{~N}_{2} gives compound \mathrm{X} . \mathrm{X} is represented as

(a) \mathrm{MWe}_{6}
(b) (\mathrm{CO})_{5} \mathrm{~W}-\mathrm{Me}
(c) (\mathrm{CO})_{5} \mathrm{~W}=\mathrm{C}(\mathrm{Me}) \mathrm{OMe}
(d) (\mathrm{CO})_{5} \mathrm{~W} \equiv \mathrm{CMe}

Show answer

Answer: (c)

Report an error in ABC26IN0492

Q4 · 2005-2021 · 2 marks

Considering the quadrupolar nature of \mathrm{M}-\mathrm{M} bond in \left[\mathrm{Re}_{2}\mathrm{Cl}_{8}\right]^{2-}, the \mathrm{M}-\mathrm{M} bond order in \left[\mathrm{Re}_{2}\mathrm{Cl}_{4}\left(\mathrm{PMe}_{2}\mathrm{Ph}\right)_{4}\right]^{+} and \left[\mathrm{Re}_{2}\mathrm{Cl}_{4}\left(\mathrm{PMe}_{2}\mathrm{Ph}\right)_{4}\right] respectively are

(a) 3.0 and 3.0
(b) 3.0 and 3.5
(c) 3.5 and 3.5
(d) 3.5 and 3.0

Show answer

Answer: (d)

Report an error in ABC26IN0493

Q5 · 2005-2021 · 2 marks

The correct classification of [\mathrm{B}_{5}\mathrm{H}_{5}]^{2-}, \mathrm{B}_{5}\mathrm{H}_{9} and \mathrm{B}_{5}\mathrm{H}_{11} respectively is

(a) closo, arachno, nido
(b) arachno, closo, nido
(c) closo, nido, arachno
(d) nido, arachno, closo

Show answer

Answer: (c)

Report an error in ABC26IN0495

Q6 · 2005-2021 · 2 marks

Metal-metal quadruple bonds are well-known for the metal

(a) Ni
(b) Co
(c) Fe
(d) Re

Show answer

Answer: (d)

Report an error in ABC26IN0499

Q7 · 2005-2021 · 2 marks

The Bronsted acidity of boron hydrides follows the order

(a) \mathrm{B}_{2} \mathrm{H}_{6}>\mathrm{B}_{4} \mathrm{H}_{10}>\mathrm{B}_{5} \mathrm{H}_{9}>\mathrm{B}_{10} \mathrm{H}_{14}
(b) \mathrm{B}_{2} \mathrm{H}_{6}=\mathrm{B}_{4} \mathrm{H}_{10}>\mathrm{B}_{5} \mathrm{H}_{9}=\mathrm{B}_{10} \mathrm{H}_{14}
(c) \mathrm{B}_{10} \mathrm{H}_{14}>\mathrm{B}_{5} \mathrm{H}_{9}>\mathrm{B}_{4} \mathrm{H}_{10}>\mathrm{B}_{2} \mathrm{H}_{6}
(d) \mathrm{B}_{5} \mathrm{H}_{9}>\mathrm{B}_{4} \mathrm{H}_{10}>\mathrm{B}_{2} \mathrm{H}_{6}>\mathrm{B}_{10} \mathrm{H}_{14}

Show answer

Answer: (c)

Report an error in ABC26IN0500

Q8 · 2005-2021 · 2 marks

White phosphorus, \mathrm{P}_{4}, belongs to the

(a) closo system
(b) nodo system
(c) arachno system
(d) hypho system

Show answer

Answer: (b)

Report an error in ABC26IN0501

Q9 · 2005-2021 · 2 marks

The number of \mathrm{M}-\mathrm{M} bonds in \mathrm{Ir}_{4}(\mathrm{CO})_{12} are

(a) four
(b) six
(c) eight
(d) zero

Show answer

Answer: (b)

Report an error in ABC26IN0502

Q10 · 2005-2021 · 2 marks

Schrock carbenes are

(a) Triplets and nucleophilic
(b) Triplets and electrophilic
(c) Singlets and nucleophilic
(d) Singlets and electrophilic

Show answer

Answer: (a)

Report an error in ABC26IN0503

Q11 · 2005-2021 · 2 marks

The reaction between \{\mathrm{PdCl}_{4}]^{2-} and \mathrm{C}_{2}\mathrm{H}_{4} produces a new compound. Compare to free \mathrm{C}_{2}\mathrm{H}_{4}, the \mathrm{C}-\mathrm{C} bond order of the product is:

(a) between 1 and 2
(b) less than 1
(c) unaltered
(d) greater than 2

Show answer

Answer: (a)

Report an error in ABC26IN0510

Q12 · 2005-2021 · 2 marks

The product of the reaction between \mathrm{CH}_{3} \mathrm{Mn}(\mathrm{CO})_{5} and { }^{13} \mathrm{CO} is:

(a) \left(\mathrm{CH}_{3}{ }^{13} \mathrm{CO}\right) \mathrm{Mn}(\mathrm{CO})_{5}
(b) \left(\mathrm{CH}_{3} \mathrm{CO}\right) \mathrm{Mn}(\mathrm{CO})_{4}\left({ }^{13} \mathrm{CO}\right)
(c) \left({ }^{13} \mathrm{CH}_{3} \mathrm{CO}\right) \mathrm{Mn}(\mathrm{CO})_{5}
(d) \mathrm{CH}_{3} \mathrm{Mn}(\mathrm{CO})_{4}

Show answer

Answer: (b)

Report an error in ABC26IN0513

Q13 · 2005-2021 · 2 marks

The number of terminal carbonyl groups present in \mathrm{Fe_2(CO)_9} is

(a) 2
(b) 5
(c) 6
(d) 3

Show answer

Answer: (a)

Report an error in ABC26IN0514

Q14 · 2005-2021 · 2 marks

An intermediate formed during the hydroformylation of olefins using \mathrm{Co_2(CO)_8} as catalyst is

(a) \mathrm{HCo(CO)_6}
(b) \mathrm{H_4Co(CO)_3}
(c) \mathrm{H_2Co(CO)_4}
(d) \mathrm{HCo(CO)_4}

Show answer

Answer: (b)

Report an error in ABC26IN0515

Q15 · 2005-2021 · 2 marks

Decarbonylation reaction of \left[\right. cis \left.-\left(\mathrm{CH}_{3} \mathrm{CO}\right) \mathrm{Mn}\left({ }^{13} \mathrm{CO}\right)(\mathrm{CO})_{4}\right] yields \mathrm{X}, \mathrm{Y} and Z , where \mathrm{X}=\left[\left(\mathrm{CH}_{3}\right) \mathrm{Mn}\right. \left(\mathrm{CO})_{5}\right] ; \mathrm{Y}=\left[\mathrm{cis}-\left(\mathrm{CH}_{3}\right) \mathrm{Mn}\left({ }^{13} \mathrm{CO}\right) \mathrm{CO}_{4}\right] ;\left[\mathrm{Z}=\operatorname{trans}-\left(\mathrm{CH}_{3}\right) \mathrm{Mn}\left({ }^{13} \mathrm{CO}\right)(\mathrm{CO})_{4}\right] The molar ratio of the products (\mathrm{X}: \mathrm{Y}: \mathrm{Z}) in this reaction is

(a) 1: 1: 1
(b) 1: 2: 1
(c) 1: 1: 2
(d) 2: 1: 1

Show answer

Answer: (b)

Report an error in ABC26IN0516

Q16 · 2005-2021 · 2 marks

According to polyhedral electron count rule, the structure of \mathrm{Rh}_{6}(\mathrm{CO})_{16} is:

(a) closo
(b) nido
(c) arachno
(d) hypho

Show answer

Answer: (a)

Report an error in ABC26IN0517

Q17 · 2005-2021 · 2 marks

An example of nido-borane from the following is

(a) \mathrm{B}_{4} \mathrm{H}_{10}
(b) \mathrm{B}_{6} \mathrm{H}_{10}
(c) \mathrm{B}_{6} \mathrm{H}_{12}
(d) \mathrm{B}_{8} \mathrm{H}_{14}

Show answer

Answer: (b)

Report an error in ABC26IN0518

Q18 · 2005-2021 · 2 marks

The reaction of \left[\mathrm{Cp}_{2} \mathrm{TaMe}_{2}\right] \mathrm{I}\left(\mathrm{Cp}=\mathrm{C}_{5} \mathrm{H}_{5}^{-}\right)with NaOMe yields.

(a) \left[\mathrm{Cp}_{2} \mathrm{Ta}(\mathrm{OMe})_{2}\right] \mathrm{I}
(b) \left[\mathrm{Cp}_{2} \mathrm{Ta}(\mathrm{Me}) \mathrm{OMe}\right] \mathrm{I}
(c) \mathrm{Cp}_{2} \mathrm{Ta}(\mathrm{Me})=\mathrm{CH}_{2}
(d) \mathrm{Cp}_{2} \mathrm{Ta}(\mathrm{OMe})=\mathrm{CH}_{2}

Show answer

Answer: (c)

Report an error in ABC26IN0519

Q19 · 2005-2021 · 2 marks

A monst the following, the metal carbonyl species having the highest v_{\mathrm{CO}} stretching frequency is

(a) \left[\mathrm{Mn}\left(\mathrm{CO}_{6}\right]^{+}\right.
(b) \mathrm{Cr}(\mathrm{CO})_{6}
(c) \left[\mathrm{V}(\mathrm{CO})_{6}\right]^{-}
(d) \left[\mathrm{Fe}(\mathrm{CO})_{4}\right]^{2-}

Show answer

Answer: (a)

Report an error in ABC26IN0520

Q20 · 2005-2021 · 2 marks

The correct order of thermal stability for the given compounds is

(a) \mathrm{TiMe}_{4}>\mathrm{Ti}\left(\mathrm{CH}_{2} \mathrm{CMe}_{3}\right)_{4}>\mathrm{TiEt}_{4}
(b) \mathrm{TiEt}_{4}>\mathrm{Ti}\left(\mathrm{CH}_{2} \mathrm{CMe}_{3}\right)_{4}>\mathrm{TiMe}_{4}
(c) \mathrm{TiMe}_{4}>\mathrm{TiEt}_{4}>\mathrm{Ti}\left(\mathrm{CH}_{2} \mathrm{CMe}_{3}\right)_{4}
(d) \mathrm{Ti}\left(\mathrm{CH}_{2} \mathrm{CMe}_{3}\right)_{4}>\mathrm{TiMe}_{4}>\mathrm{TiEt}_{4}

Show answer

Answer: (d)

Report an error in ABC26IN0521

Q21 · 2005-2021 · 2 marks

An efficient catalyst for hdrogenation of alkenes is \left[\mathrm{Rh}\left(\mathrm{PPh}_{3}\right)_{3} \mathrm{Cl}\right]. However, \left[\operatorname{Ir}\left(\mathrm{PPh}_{3}\right)_{3} \mathrm{Cl}\right] does not catalyze this reaction, because

(a) \mathrm{PPh}_{3} binds stronger to Ir than to Rh
(b) Cl binds stronger to Ir than to Rh
(c) \mathrm{PPh}_{3} binds stronger to Rh than to Ir
(d) Cl binds stronger to Rh than to Ir

Show answer

Answer: (a)

Report an error in ABC26IN0523

Q22 · 2005-2021 · 2 marks

When one CO group is replaced by \mathrm{PPh}_{3} in \left[\mathrm{Cr}(\mathrm{CO})_{6}\right], which one of the following statement is TRUE?

(a) The \mathrm{Cr}-\mathrm{C} bond length increases and CO bond length decreases
(b) The \mathrm{Cr}-\mathrm{C} bond length decreases and CO bond length decreases
(c) The Cr-C bond length decreases and CO bond length increases
(d) The Cr-C bond length increases and CO bond length increases GATE 2016

Show answer

Answer: (c)

Report an error in ABC26IN0524

Q23 · 2005-2021 · 2 marks

The structure type and shape of the polyhedral (skeletal) framework of the carborane \mathrm{Me}_{2}\mathrm{C}_{2}\mathrm{B}_{10}\mathrm{H}_{10}, respectively, are

(a) nido and dodecahedron
(b) closo and icosahedron
(c) nido and icosahedron
(d) closo and dodecahedron

Show answer

Answer: (b)

Report an error in ABC26IN0528

Q24 · 2005-2021 · 2 marks

Based on Wade's rule, the structure-type of \left[\mathrm{B}_{5} \mathrm{H}_{8}\right]^{-}is

(a) closo
(b) nido
(c) arachno
(d) hypho

Show answer

Answer: (b)

Report an error in ABC26IN0529

Q25 · 2005-2021 · 2 marks

The reaction of equimolar quantities of \mathrm{Fe}(\mathrm{CO})_{5} and \mathrm{OH}^{-}gives a complex species X which on further reaction with \mathrm{MnO}_{2} give species Y. X and Y, respectively, are

(a) \left[\mathrm{Fe}(\mathrm{CO})_{5}(\mathrm{OH})\right]^{-}and \mathrm{Fe}_{2}(\mathrm{CO})_{9}
(b) \left[\mathrm{Fe}(\mathrm{CO})_{4}\right]^{2-} and \mathrm{Mn}_{2}(\mathrm{CO})_{10}
(c) \left[\mathrm{HFe}(\mathrm{CO})_{4}\right]^{-}and \mathrm{Fe}_{2} \mathrm{O}_{3}
(d) \left[\mathrm{HFe}(\mathrm{CO})_{4}\right]^{-}and \mathrm{Fe}_{3}(\mathrm{CO})_{12}

Show answer

Answer: (d)

Report an error in ABC26IN0530

Q26 · 2005-2021 · 2 marks

The metal borides that contain isolated boron atoms are:

(a) \mathrm{Ti}_{4} \mathrm{~B}_{4} and \mathrm{V}_{3} \mathrm{~B}_{4}
(b) TiB and HfB
(c) \mathrm{Tc}_{7} \mathrm{~B}_{3} and \mathrm{Re}_{7} \mathrm{~B}_{3}
(d) \mathrm{Cr}_{5} \mathrm{~B}_{3} and \mathrm{V}_{3} \mathrm{~B}_{2}

Show answer

Answer: (c)

Report an error in ABC26IN0539

Q27 · 2005-2021 · 2 marks

The \mathrm{Mo}-\mathrm{Mo} bond order in \left[\left(\eta^{5}-\mathrm{C}_{5} \mathrm{H}_{5}\right) \mathrm{Mo}(\mathrm{CO})_{2}\right]_{2} which obeys the 18-electron rule is ____ . ORGANOMETALLIC COMPOUNDS

Show answer

Answer: 3

Report an error in ABC26IN0540

Prepare with the GATE batch

Every PYQ is discussed live in the batch. See the course or call +91 92121 42427.

Questions from the ABC Question Bank, typed from the official papers. A question whose answer is still under review is not shown.