A special class of compounds in which a electron deficient central atom (usually a metal ion) is bonded to many electron donors called ligands. These compounds are highly stable and are widely found in nature. They also have a wide variety of industrial applications.

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How many different possible structures (isomers) are there for the complex, [Mn(OH2)3(NH3)3] 3+?

How many different possible structures (isomers) are there for the complex, $\ce{[Mn(OH2)3(NH3)3]^{3+}}$? I really don't know how to begin with this. I know the answer is 2, but i don't have the ...
2
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1answer
39 views

Why does Co2+ have 7 electrons in the 3d orbital, and not 5 like Mn?

I'm taking general chemistry 2 this half of the summer. We are currently going over coordination complexes, ligands and transition metal ions. In particular, this question is in regards to the ligand ...
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1answer
36 views

How many ligands in Heme?

How many ligands does Fe has in heme ? I am not sure how many are in heme and how many in cytochrome C. Its about iron complexes.
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1answer
96 views

In the lattice model, what's a nearest neighbor?

I was reviewing my grad Thermodynamics textbook to go over a concept that I never learned well: the Lattice model. One set of equations1 has: $zN_1=2N_{11}+N_{12}$ $zN_2=2N_{22}+N_{12}$ where $z$ ...
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1answer
35 views

square planar geometry in metal complex

I don't understand what this statements wants to say, "Square planar geometry is favoured by ligands that can form pi bonds by accepting electrons from metal atoms or ions" How is this possible I ...
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43 views

Coordination number for $\ce{BeCl2}$

I am confused, should it be 2 or 4? If I consider $\ce{BeCl2}$ as a chain structure the coordination number is 4, and in the gas phase it is 2. Please, could you give an explanation for this?
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1answer
37 views

Electride salt preparation

In preparation for the Birch reduction, I am trying to prepare an electride salt, [Na(NH3)6]+, e-. This salt should be brilliant blue, as far as I know, but I am getting a black sludge when adding ...
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0answers
55 views

Co(H₂O)₆ , a low spin coordination complex,why?

Despite $\ce{H2O}$ being a weak field ligand, why is $\ce{[Co(H2O)6]^3+}$ a low spin complex?
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1answer
26 views

Which d-block cation has the maximum hydration enthalpy?

Among $Mn^{2+}, V^{2+}, Ni^{2+},$ and $Ti^{2+},$ which cation is having the highest hydration energy to form the aqua complex $[M(H_2O)_6]^{2+}$ My approach: I guess $Mn^{2+}$ should be the answer as ...
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1answer
96 views

The bond in coordination complexes

This is a very basic question and I'm surprised it only just struck me. The nature of the bond in coordination complexes is a coordinate covalent bond. Only the ligand donates electrons for bond ...
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2answers
60 views

Heating CrCl3(Bipy)3 (undergraduate exam question)

CrCl3(Bipy)3 (A) when heated forms (B) which has the formula CrCl3(Bipy)2 and has one free Cl- per mole of (B) (Not given in question but i don't need help with the gravimetric analysis bit, just take ...
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1answer
155 views

Structure of Fe1C13H10O2

The reaction of $\ce{(C5H5)Fe(CO)2Cl}$ with an equimolar amount of $\ce{Li+[C6H5]-}$ gives a product. Draw its structure and apply the 18 electron rule. In a question I was given the ...
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1answer
76 views

Zinc Picolinate - Positive, negative or neutral charge?

I'm going to be using a finings agent with a positive charge to remove negative trub from a solution (beer). I would like to keep some chelated zinc in the solution - ideally zinc picolinate - so ...
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1answer
59 views

Different coloured chromium salts

Evaporating cold aqueous chromium(III) chloride produces violet crystals. However when hot aqueous chromium(III) chloride crystallizes, green crystals result. Could someone please explain the ...
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2answers
246 views

Transition metal complex question

I am given a blue solid W and it contains a tetraammine copper(II) complex and a ${SO_4}^{2-}$ . I added dilute sulphuric acid until the solution is pale blue; then added potassium iodide solution. A ...
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1answer
103 views

How is an aqueous Ag+ the same as [Ag(H2O)2]+?

$\ce{Ag^{+}_{(aq)}}$ can be written as $\ce{[Ag(H2O)2]+}$ but how would you know that it bonds with 2 water molecules? I don't get when ligands randomly form 6, 4, 2 bonds.
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1answer
113 views

What are the products of [Ti(H2O)6]Cl3 + H2SO4 + K2Cr2O7 --->

Im slightly lost on how to proceed with this equation. I know potassium dichromate is a strong oxidizing agent but im unsure of how to deal with it along with the titanium complex complex. Was ...
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1answer
107 views

Predicting bond-strength of metal carbonyls

The metal carbonyls (and similar organometallic compounds) involve a combination of sigma bond, a pi bond and backbonding. The bond strengths under consideration are the metal-carbon bond and the ...
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1answer
71 views

Ligand exchange reactions… are they one way or reversible?

Are ligand exchange reactions one-way reactions or reversible? I know this is a very silly question but its not said outright in any place... For example, in my high school chemistry book, these two ...
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2answers
184 views

Colours and transition metals

From my book: "When white light shines through a solution of a complex ion of a transition metal, photons of a particular frequency are absorbed and their energy promotes an electron from lower ...
4
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1answer
78 views

Splitting of $d$ orbitals when ligands approach central metal ion

In my high school chemistry book, it is written that when ligands approach the central metal ion (transition metal ion) to form dative bonds, the $3d$ orbitals split into two: two which are in higher ...
3
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1answer
121 views

How can different no. of unpaired electrons lead to different colours of co-ordination compounds?

To make the question clear I would like to take an example. $\ce{K_3[Fe(CN)6]}$ and $\ce{K3[FeF6]}$ shows different colors in solutions. It is given in my textbook that it is because of different ...
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1answer
37 views

Does deprotonation of a hexaaquaion continue until neutral charge

I learned that deprotonation is the process in which a proton is lost from ligand $\ce{H2O}$ molecules surrounding a central metal ion (I am referring to hexaaqua ions). Also, the process continues ...
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1answer
1k views

Werner's theory and complex salts

According to Werner's theory, metal ions have two types of valency-primary and secondary, where the primary valency is said to be satisfied by negative ions only, and the secondary valency can be ...
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1answer
59 views

Does chelation take ions out of solution

Does EDTA take $\ce{Mg^{2+}}$ and $\ce{Mn^{2+}}$ out of solution, so that it can be removed by a filter? Or does it just take it out of any chemical reactions going on in the solution?
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2answers
350 views

Potassium permanganate hybridisation

I'm clear with the concepts of crystal field theory. But I can't point out the exact reason why is the hybridisation of potassium permanganate ($\ce{KMnO4}$) is $d^3s$. Can anyone explain please?
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1answer
84 views

Which d-orbitals split according to CFT?

According to CFT, the degenerate d-orbitals split into $eg$ and $t_2 g$ groups. Are these the outermost nd orbitals which are vacant(4-d in case of 4th period) or the penultimate filled (n-1)d ...
3
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2answers
224 views

Why Cl- can't act as bidentate ligand?

Cl- is a monodentate ligand. It has four lone pairs then why it can't donate two lone pairs to central atom and act as a bidentate ligand?
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1answer
94 views

Difference between sodium ion and a transition metal ion dissolving in water?

In class, I learned that when $\ce {NaCl}$ is dissolved in water, the partially negative oxygen part of the water molecules surround the Na+ ion and energy is given off (hydration enthalpy) Likewise, ...
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1answer
85 views

Formation of coordination complexes?

I'm having trouble understanding how exactly coordination complexes are formed. Compounds such as $\ce{[Cu(H2O)6]++}$ are the ligands filled into the empty 3 of 4p orbitals+ 1 of 5s orbital + 2 of ...
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1answer
111 views

If I add some KOH, where will the reaction shifts?

I just got a final test and one of the question is: $\ce {Ni^2+}$ + 6$\ce{NH_3}$ $\ce {<=>}$ $\ce{[Ni(NH3)6]^2+}$ If we add some aqueous $\ce{KOH}$ after the reaction reach equilibrium, where ...
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0answers
135 views

Magnetic moment of coordination complexes?

To understand the commonly quoted magnetic values of coordination complexes (central ion) we use $$m_l=\sqrt{n(n+2)} \text{BM where BM}=\frac{e\hbar}{2m_e}\text{JT}^{-1}$$ $n$=number of unpaired ...
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1answer
230 views

What is the number of unpaired electrons in [Co(SCN)₄]²â»?

Find the number of unpaired electrons present in the d orbital (whose lobes are present along the axis) for the complex $\ce{[Co(SCN)4]^{2-}}$. Since $\ce{SCN}$ is a weak ligand I did not pair ...
3
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1answer
137 views

Symmetry and stability of a molecule (Jahn-Teller Distortion)

I've taught in my class that if a molecule posses high degree of symmetry it's stability will be more,in other words symmetry and stability are directly proportional. Is this statement correct? And if ...
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2answers
6k views

How to calculate crystal field stabilisation energy?

How to calculate it? I know that it depends on the coordination compound and the number of electrons present in t2g and eg orbitals and the final answer is expressed in terms of crystal field ...
3
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1answer
300 views

Are there positive ligands?

Are there positive ligands which can bind to the central metal atom to form co-ordination compounds? $My$ $thoughts:$I know that ligands are Lewis bases which donate a pair of electrons and the ...
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1answer
819 views

Is there a mnemonic to study the spectrochemical series?

Mnemonics help to by-heart things which are difficult to do so and which are important. I found mnemonics for studying the periodic table, electromagnetic series etc which were of great help.So, is ...
3
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1answer
127 views

Oxidation state of metal in metal oxo complexes always positive?

Do all metals in metal oxo complexes (eg $\ce{Fe}$ in Ferrate, $\ce{Mo}$ in $\ce{MoO4}$,...) have positive oxidation states?
2
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1answer
704 views

Optical isomerism in Co-ordination Compounds

Optical isomerism in normal organic molecules can be found out my looking for chiral carbon and and the no. of isomers can be found out by drawing different spacial orientations of the same. But, I ...
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1answer
1k views

Difference between 18 electron rule and effective atomic number rule

Is there any difference between 18-electron rule and effective atomic number rule? Both rules are based on attainment of a noble gas configuraion as a criteria for stability of complexes. Besides, ...
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1answer
206 views

Geometrical Isomerism of Metal Complex

Does $\ce{Ni((en)2(Cl)2)}$ show cis-trans form ? And if No Why not ?
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1answer
260 views

What Could Formations of Linkage Isomers of [Co(NH3)NO2]^2+ be like ?

I am trying to draw the structure of this complex [Co(NH3)NO2]^2+ ,however I am not sure if the linkage isomers of this complex like this ;
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1answer
1k views

Total magnetic moment of atom

Whenever I read about coordination compounds in my textbooks, I always find a discussion about spin-only magnetic moment which is given by $\sqrt{n(n+2)}$ BM, Where $n$ is the number of unpaired ...
3
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1answer
90 views

Strongest chloride complex as perdicted by HSAB theory

Why won't $\ce{Ni^2+}$ form a complex with $\ce{Cl-}$, while the ions $\ce{Cu^2+}$ and $\ce{Co^2+}$ form the complexes $\ce{[CuCl4]^2-}$ and $\ce{[CoCl4]^2-}$? According to the HSAB theory, ...
2
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1answer
194 views

Which d-orbital configurations form an octahedral complex?

With reference to crystal field splitting in octahedral complexes, my textbook shows the following table of distribution of $d$-orbital electrons in octahedral complexes, based on the energy ...
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1answer
224 views

Bonding in a bridged metal carbonyl

Can someone please explain the bonding in a bridged metal carbonyl (like diiron nonacarbonyl)? I cannot understand what kind of bonds (sigma/pi) exist between the bridging carbonyls and the metals. ...
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1answer
328 views

What does the eta notation mean in the naming of a transition metal complex?

I am reading a paper (Gutel et al., J. Mater. Chem. 2007, 17, 3290-3292) and I have come across the following reaction: In organic solvents, the decomposition under mild conditions of ...
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2answers
4k views

Why do transition elements make colored compounds?

Why do transition metals element make colored compound both in solid form and in solution? Is it related with their electrons or something else?
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6k views

Tetrahedral or Square Planar

How can one predict whether a given complex ion will be square planar or tetrahedral when its coordination number is 4 using crystal field theory ? Is it possible to theoretically predict this?
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3answers
2k views

Normal Spinel and Inverse Spinel

According to my notes, [OCTAHEDRAL SITE STABILIZATION ENERGY (OSSE)], sterical effects and electronic effects in stability create a confusion in this theory. However, we are able to solve this problem ...