Top 5 Tricky Questions in organometallic compound| Inorganic chemistry

Organometallic chemistry topic is very important for CSIR-NET GATE IIT JAM correspond to other entrance examination like DRDO, NTPC, SET, IISc, TIFR..

Organometallic Chemistry-4| Inorganic

Hello, everyone today we will discuss the top five tricky questions in organometallic chemistry with a solution pdf. Continue to the session for entrance examination aspirants or research fellows or any work-in-project students. Who can see this Question-answer session and inspire and practice? We have already solved a few topics earlier you can go through click here and read the post on organometallic chemistry. The top question solves earlier in this section check it.

What for?

Organometallic chemistry topic is very important for CSIR-NET GATE IIT JAM correspond to other entrance examination like DRDO, NTPC, SET, IISc, TIFR, BARC, ONGC, and different national levels completive examination. Or it is a very important GRE (Graduate Record Examination) Test subject chemistry in the USA.

Organometallic chemistry and catalyst are special topics in the (GRE) Graduate Record Examination Chemistry Test. So read and practice with a friendly test book and content.

What are the best study materials for organometallic chemistry?

Before reading any Chemical science topic-wise complete solution book, read our article solve itself which helps you with lots of information. One thing reminds me that before reading our article must read any textbook available in the market which is clear about your basic concept of organometallic compound-related. That is very important. Or one thing is that the books or any study materials must be relevant to your exam perspective.

That is why we suggest the best books on organometallic and bioinorganic chemistry combined by Ajai Kumar. This book is pretty good for a beginner as well as advanced-level students. Or Organometallic chemistry BD Gupta. Or Inorganic chemistry Hyuee Keter Keter.

Those books help you from beginner level to advance level. Now come back to the main point or the primary goal of this article, we have to main motive to provide good quality question-answer solutions that help students in practicing topic-wise.

Top 5 Question Solution on organometallic chemistry:

Before reading the solution try it yourself. And after solving match your answer and what trick you apply. If any mistakes or any wrong concepts or wrong approaches are used in your answer paper, write them down in the notebook and go forward. That helps you what is a mistake by you. And how to solve it.

So, let’s started the question-answer session:

Q.15. The oxidative addition and reductive elimination steps are favored by

(A) Electron-rich metal

(B) Electron-deficient metal centers

(C) Electron-deficient and electron-rich metal centers respectively

(D) Electron-rich and electron-deficient metal centers respectively.

Answer: Correct answer is (D) Electron-rich and electron-deficient metal centers respectively


In Oxidative addition increase +2 unit of the oxidation state of the metal complex (Ex: M+ to M2+  or M2+ to M4+ ). If the oxidation state does not charge any addition this is called only addition, not oxidative addition.

Condition of oxidative addition:

What happens to oxidative addition?

  • The electron count is increased by 2 units.
  • The coordination number is increased.
  • The oxidation state of the metal is increased by +2 units.

The reaction mechanism of oxidative addition metal complex forms a stable intermediate and stability follows the 18 electrons rules.

Conclusion of oxidative addition reaction:


  • In oxidative addition, metal should be electron rich.
  • High electron density metal should be attacked fast comparatively low electron density metal.
  • Metal should be coordinatively unsaturated. (Coordination number of metal less than 6).
  • d8 and d10 metal fast rate of oxidative addition. Whare d8 is Squar planer (C.N. = 4 <6) and d10 metal rapid rate of oxidative addition due to high electron density (electron-rich).
  •  d0 does not participate in oxidative addition reactions due to electron deficiency.
  • The electron-withdrawing group (EWG) or ligand (pi acceptor ligand) decreases the rate of oxidative addition. Due to making an electron-deficient metal.
  • The electron donating group (EWG) or Ligand (Pi donating ligand) increases the rate of oxidative addition. Due to making an electron-rich metal.

Q.16.  Identify the order for increasing the stability of the following organometallic compounds, TiMe4, Ti(CH2Ph) 4, Ti(i-Pr) 4, and TiEt4.

(A) Ti(CH2Ph) 4  < Ti(i-Pr) 4 < TiEt4 <TiMe4

(B) TiEt4 < TiMe4 < Ti(i-Pr) 4 < Ti(CH2Ph) 4 

(C) Ti(i-Pr) 4 < TiEt4 < TiMe4 < Ti(CH2Ph) 4

(D) TiMe4 < TiEt4 < Ti(i-Pr) 4 < Ti(CH2Ph) 4

Answer:  Correct answer is (C) Ti(i-Pr) 4 < TiEt4 < TiMe4 < Ti(CH2Ph) 4


Q.17.  Among the metals, Mn, Fe, Co, and Ni, the ones that would react in their native form directly with CO-giving metals carbonyl compounds are

(A) Co and Mn              (B) Mn and Fe

(C) Fe and Ni                (D) Ni and Co



Q.18. In the hydroformylation reaction, the intermediate CH3CH2CH2Co(CO) 4

(A) Form an intermediate acyl CH3CH2CH2COCo(CO)3

(B) Forms an adduct with an olefine reactant.

(C) Reacts with H2

(D) Elimination of propane

Answer: the correct answer is (A) Form an acyl intermediate CH3CH2CH2COCo(CO)3


Q.19. The number of metal-metal bonds in the dimers [CpFe(CO)(NO)] 2 and [CpMo(CO) 3] 2 respectively, are

(A) two and two             (B) two and three

(C) One and two            (D) zero and one

Answer: the correct answer is (D) zero and one


Bonus question:

Q.20. In the trans-PtCl2L(CO) complex, the CO stretching frequency for L = NH3, pyridine, and NMe3 decreases in the order

(A) pyridine > NH3 > NMe3        (B) NH3 > pyridine > NMe3

(C) NMe3 > NH3 > pyridine        (D) pyridine > NMe3 > NH3

Answer: Correct answer is (A) pyridine > NH3 > NMe3


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