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For questions about the characteristic physical properties, chemical reactions, etc. of d-block elements, group 3-12, or their compounds. Do not use this tag if your questions is about general properties of metals, use [metal] instead. Also see [rare-earth-elements].

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Dilute FeCl3 colour is darker at 5e-4M than at 5e-3M. Why?

I did two different dilutions of $\ce{FeCl3}$ (within a $\pu{1h}$ timespan) from $\pu{0.05 M}$, and the one with $\pu{5E-4 M}$ concentration looked a darker orange than the one with $\pu{5E-3 M}$. ...
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0answers
40 views

Why is t2g level above eg level in octahedral d4 complexes in orgel diagram?

I am taking an introductory course in chemistry. This picture was there in my lectures, i am bit confused i thought the t2g level were lower than eg in presence of a weak octahedral field but it is ...
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0answers
12 views

Is the Dewar-Chatt-Duncason model limited to bonding between only alkenes and a metal?

Most of what I have read states that the DCD model only consists of the alkene and the metal. Can only alkenes (C=C) bond with a metal pi complex in context of the DCD model? Or does the DCD model ...
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12 views

Why do d block elements having same number of unpaired electrons show different colours?

The colour of a transition element depends upon number of unpaired electrons.V^+3 has two electrons impaired ,Ni^+2 also has 2 unpaired electrons.But both of them show different colours?
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1answer
31 views

Oxidation state in transition metals

Why does scandium has +2 oxidation state unstable? It only has +3 oxidation state stable. Scandium has outermost electronic configuration as 3d¹4s². Why it does not lose two 4s e- only instead of all ...
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0answers
84 views

Why Cu has higher melting point than Ag and Au?

Actual trend in transition metal is M.P. of 5d series > M.P. of 4d series> M.P. of 3d series. But I don't understand why there is an anomaly in the case of 11 the group.
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0answers
24 views

Rhombohedral second-order Jahn–Teller effect in Au(II) complex?

I was recently listening to a talk about the following work[1] when the author mentioned that they explained the following. In this $\ce{Au(II)}$-porphyrin complex you observe two sets of $\ce{Au-N}$ ...
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0answers
95 views

Molecular orbital diagram for terminal metal-oxo complex with dative bonds

I am interested in terminal metal-oxo complexes and their electronic structure, specifically those with coordination numbers of 6, including the oxo ligand. I know that Fe(IV)-oxo complexes tend to ...
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0answers
42 views

Why doesn't rose gold tarnish?

I was looking into rose gold, and I was wondering how long it takes for the alloy to tarnish. The results I got from a couple sites state it doesn't. One of them said, however, it develops this patina....
0
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1answer
32 views

precipitation reaction - cellulose in schweizer reagent reacts with acid

In the regeneration of dissolved cellulose (in a cuprammonium solution) in an acid bath, say sulphuric acid, what is the chemical reaction? There is a lot about the chemistry of the production of the ...
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21 views

Breakdown of LaPorte Rule in tetrahedral transition metal complexes

What is the percentage of d-p mixing in tetrahderal complexes? Is there a way to figure out the exact wavefunctions of different orbitals of a transition metal ion in a transition metal compound?
3
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1answer
100 views

Which karat gold is harder, 24 kt or 18 kt?

$\pu{24 kt}$ gold indicates that $24/24$ part of it, i.e. $100\%$ of it is gold. $\pu{18 kt}$ indicates that $18/24$ part of it is gold. As gold is a soft element, I reckoned that $\pu{18 kt}$ gold ...
3
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1answer
176 views

Considering the d-d transition how, does tetracyanidonickelate(II) ion exist as a colored complex?

As I refer on google, the resources indicated that, the d block elements which have unpaired electrons as in their ions, when they are making complexes with ligands, they can absorb different ...
4
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2answers
59 views

Transition metal or transition element?

With reference to the periodic table’s d-block, are the terms “transition metals” and “transition elements” interchangeable when describing these elements? Are there any situations where it would be ...
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1answer
152 views

Why do NON -Transition elements exhibit variable oxidation state?

I know transition elements exhibit variable oxidation states because valence electrons are in d block and s which are very close so they have similar energies ,thus with slightly different energies ...
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0answers
170 views

Compare stability of transition metal cations in aqueous solution

I have to compare the stability of the following transition metal cations: $\ce{Co^3+, Fe^3+, Cr^3+, Sc^3+}$ in aqueous solution. (Source: Joint Entrance Exam (JEE) 2013 Mains India) The first thing ...
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1answer
139 views

Does tetraoxidovanadium (VO4+) ion exist?

In my book (NCERT India), it is mentioned that: (page 224) ...$\ce{Mn2O7}$ gives $\ce{HMnO4}$ and $\ce{CrO3}$ gives $\ce{H2CrO4}$ and $\ce{H2Cr2O7}$. $\ce{V2O5}$ is, however, amphoteric though ...
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1answer
378 views

Colour of the transition metal complexes [closed]

I read in my Chemistry AP class that the colour of the transition metal complexes is due to the wavelength of the visible light that is left unabsorbed, when the d subshell is split due to the ...
2
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1answer
137 views

ligand pi system irreducible representation for trigonal bipyramidal transition metal complex

I am considering a D$_{3h}$ trigonal bipyramidal transition metal complex MX$_5$. I have found that the irreducible representation for the ligand s and $\sigma$ systems is 2A$_1'$+A$_2''$+E$'$. I ...
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192 views

Meaning of - “Redox Potential of Vanadium 2+/3+ Has Low Value”

This site mentions: The lower value for Vanadium is due to the stability of $\ce{V^2+}$ as it has a half-filled $t_{2g}$ level If $\ce{M^3+}/\ce{M^2+}$ is low, it means $\ce{M^3+}$ is more stable ...
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1answer
54 views

What are the magnetic properties of [Ni(S2C2Ph2)2]^z's 3 oxidation states?

I was doing some research on Wikipedia and I came across the article on non-innocent ligands. It talked about the chemical $$[\ce{Ni(S_2C_2Ph_2)_2}]^z$$ as an example. It mentioned that the transition ...
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0answers
69 views

Color of potassium permanganate and potassium dichromate [duplicate]

In $\ce{KMnO4}$, the Oxidation state of $\ce{Mn}$ is +7, which results in an electronic configuration as $\ce{[Ar] 4s^0 3d^0}$ In $\ce{K2Cr2O7}$,the Oxidation state of $\ce{Cr}$ is +6, which results ...
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0answers
341 views

The irregular trend in ionization enthalpy of 3d elements

The d block elements display several exceptional behaviours, and one of them is the irregular trend in ionization enthalpy of 3d elements. The reason given by my textbook is very confusing, which I'...
3
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1answer
124 views

Can we classify all the d-block elements as transition metals?

I thought that properties of d-block elements are transitional between those of s-block and p-block elements, and that is the reason for calling them transition metal. My textbook says that not all d ...
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41 views

Assignment of the NMR of a copper-oxo complex

The 1H NMR of [Cu4OCl10][Me4N]4 in DMSO has the following peaks: 3.31 ppm, medium sized 3.19 ppm, large 2.50 ppm, solvent 1.018 ppm (bump, likely just noise) Why are there two proton environments?...
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23 views

What's the difference of the emission characteristics of pyrometallurgy and hydrometallurgy processes

I have learned about that pyrometallurgy and hydrometallurgy processes are two major method to refine the metal ores for industrial applications. For some reason, I want to compare the different ...
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1answer
69 views

Is it absolutely necessary to use centrifuge to separate ethylene glycol from precipitate?

I've been trying to synthesize intermetallics of $\ce{XY}$ type using transition metal salts and main group element salts. For my system, EG, DEG, and TEG are good solvents. However, because of them ...
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0answers
23 views

Chemistry d block [duplicate]

In, transition metals, they show coloured compounds Why do some of them do not show any colour. Why ti3+ shows colour as it does not have any electron in d orbital and what is zn2+ colorless
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1answer
43 views

Thermal oxidation of gold(I) sulfide

As far as I know the chemistry of $\ce{Ag}$ and $\ce{Au}$ are almost the same; because $\ce{Ag}$ belongs to the 4d series and $\ce{Au}$ belongs to the 5d series, we know the size of 4d and 5d are ...
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260 views

Why do transition metals make colored compounds despite the remaining d orbitals being hybridized? [closed]

I know that transition metals make colored compounds when they forms a bond with a ligand, as the ligand increases the energy level of $\ce{d_{x^2-y^2}}$ and $\ce{d_{z^2}}$ orbital by repelling these ...
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2answers
191 views

Does titanium(II) oxide conduct electricity? [duplicate]

In my book, it is given that $\ce{TiO(s)}$ is an electrical conductor. But I'd think that since $\ce{TiO(s)}$ is ionic and in solid state, it shouldn't conduct electricity. So, why does it conduct ...
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1answer
160 views

Why does cobalt have no negative charge?

I would like to know why cobalt cannot have a negative charge (or at least why a negative charge for cobalt isn't typical). I am not sure where I have gone wrong in my reasoning. The electronic ...
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1answer
59 views

Is it possible to dissolve gold in zinc?

I know you can dissolve gold in mercury, but i do not have access to any. Would it be possible to dissolve it in molten zinc instead mercury.
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429 views

Why does cobalt primarily form low-spin complexes?

Why is $\ce{[Co(NH3)6]^3+}$ a low spin complex while the nickel equivalent is a high spin complex? And in general, why does cobalt have a tendency to form these low spin complexes? In "Why is ...
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73 views

How to rationalize the colour change of the thermochromic bis(diethyl-ammonium) tetrachloridocuprate(II) complex

The colour of the compound changes from deep green/green-blue to yellow upon raising the temperature. I'm trying to rationalise this by using the d-orbital splitting, but I've got myself in a logic ...
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1answer
221 views

Hydrolysis of transition metals' halides?

So, it's a relatively common known solubility rule that any hydroxide with a cation not in the first two groups is basically insoluble. So supposing we have a transition or post-transition metal $M$ ...
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0answers
108 views

How does the hexaaquacopper (II) form? [duplicate]

So the hexaaquacopper (II) ion has an octahedral structure with 6 aqua ligands datively bonded to the central Cu2+ cation: My question is: how is this possible if the electronic configuration of the ...
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0answers
82 views

Reversed trends in stability of transition metal ions with respect to oxidation state

Why is titanium more stable with a lower oxidation state, but vanadium more stable with a larger oxidation state? More specifically, why is $\ce{Ti^{+}}$ more stable than $\ce{Ti^{3+}}$, but $\ce{V^{...
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0answers
116 views

Why Mn atom show maximum valency of 4 with F atom?

Mn ($3d^5$, $4s^2$) can have maximum 7 unpaired electrons in excited state so it should have formed MnF7 molecule but it can form only MnF4 molecule. Is it because: $d_{xy}, d_{yz}, d_{zx}$ orbitals ...
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0answers
59 views

Why is the Mn(II)/Mn(0) standard reduction potential exceptionally low?

Why does $\ce{Mn^{+2}/Mn}$ have an exceptionally low $\pu{E^o}$ value? Is it because of the lesser delocalization of electrons, or the stable $\ce{Mn^{+2}}$ showing a resistance to change? Does it ...
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2answers
69 views

Why does it yield iron(II) chloride instead of iron when copper meets iron(III) chloride? [closed]

Complete the equation: $$\ce{Cu + FeCl3 -> ? + ?}$$ I wrote $\ce{CuCl2}$ and $\ce{Fe}$, but it turned out to be $\ce{Cu}$ and $\ce{FeCl2}$. I really wonder why.
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767 views

reduction of Fe3+ to Fe2+ in (slightly) oxidated FeCl2 solution

I am doing some experiments with Fe2+ to create nano crystals (in aqueous solution) but Fe3+ is messing with my experiment. I was planning to use some Zinc (which I'll need to order from VWR or Sigma) ...
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302 views

Why does Zinc not have magnetic properties despite it being a transition element?

I know Zinc has a full d-orbital which might contribute to the effect. But it is not ferromagnetic or paramagnetic like other transition element complexes. Why is that?
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Trend in the infrared stretching of molecular hydrogen to group 8 transitions metals?

While going through old notes, in relation to the Dewar-Chatt-Duncanson model, it states that the stretching frequency for $\ce{N2}$ to the group 8 transition metals ($\nu(\ce{NN})$) proceeds as: \...
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1answer
184 views

electron counting for transition metal-oxo ligand compound

Using donor-pair method, how many electrons would an oxo ($O^{2-}$) ligand contribute? I cannot decide if it is 2 or 4.
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0answers
190 views

Reduction potential of a complex

I am given the reduction potential of $\ce{Fe^{3+}}$ to $\ce{Fe^{2+}}$ as well as the dissociation constants $\ce{K_D}$ for a $\ce{Fe^{3+}}$ complex and a $\ce{Fe^{2+}}$ complex (effectively, the ...
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30 views

Cytotoxicity of Ru-complexes

I have a basic question: why are Ru(II)-complexes cytotoxic? What I know is that depending on the used ligand some of them interact with the DNA either via DNA-pi-stacking (intercalation) or binding ...
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0answers
62 views

Why is the copper in my pan magnetic?

My Momma bought a copper pan made for induction because it was the only one she could find that she wanted and was big enough to pan fry half a chicken. But I noticed something odd about the copper. ...
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0answers
318 views

Rationalising the trend of standard electrode potentials between the +II and +III oxidation state of first-row transition metals

Trends in standard electrode potentials of d block elements: An examination ofthe $E^0 (\ce{M^3+}/\ce{M^2+})$ values (Table 8.2) shows the varying trends. The low value for Sc reflects the ...
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1answer
99 views

Why are aqua ion complexes of transition elements not solid but a solution? [closed]

Water ligands form dative covalent bonds with the central transition metal ion. That would mean a molecule is formed, just like sulfur dioxide or any other. The transition metal ion does not form ...