Questions regarding the d-block elements, group 3-12.

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Why Does Coordination of Metal Ions Happen Anyways?

I've been studying coordination chemistry, but I still have a fundamental question about the area: why do transition metals even form coordination compounds, while main group metals do not? Why can't ...
4
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1answer
52 views

Why is platinum an excellent catalyst in comparison with similar metals? [duplicate]

What is special about platinum structure which actively participate in catalytic reactions while similar metals with similar atomic structures cannot.
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5 views

Nickel(II) + borohydride debenzylation reaction mechanism

I've been looking at this reaction for cleavage of benzyl esters. I've also looked at the original paper and some others, but haven't been able to find any mechanism on how this reagent does ...
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1answer
50 views

Does crystal field splitting energy Δ increase going down a group of transition metals if the ligands are weak field?

Going down a group, the metal orbitals are more diffuse so there is greter overlap between the metal and the ligand orbitals. If there are no π-interactions, i.e. with σ-donor ligands like ...
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37 views

d-d transitions vs charge transfer transitions

I have the following questions for one of assignments: "If d-d transitions are due to electrons moving between different d-orbitals, and "charge transfer transitions" are due to electron moving ...
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27 views

Reduction potential of Co3+/Co2+

Why is the reduction potential of Co3+/Co2+ higher than Mn3+/Mn2+ couple? What I know : EC of the ions: Looking at the ECs I can't imagine any reason for this. And Mn3+ achieves a very stable ...
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1answer
64 views

How many d-electrons are in the outer shell of the metals in following compounds: [duplicate]

How many d-electrons are in the outer shell of the metals in following compounds: ZnS Do I just use Zn^2+ and as I know that in Ions the s orbitals are removed first I count 10 d electrons? However ...
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1answer
40 views

How many d-eletrons are in the outer shell of following compounds:

How many d-electrons are in the outer shell of the metals in following compounds: $\ce{ZnS}$ and $\ce{NiS}$ So sulphur does not has any $\ce{d}$ electrons and $\ce{Zn}$ has $10\ce{d}$ electrons. ...
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0answers
8 views

Melting temperature and electronegativity trends in transition metals [duplicate]

So I know that generally the melting temperature increases across the row (let's look at just the first row for now) but what are the deviations? And why do they occur? I've looked everywhere online ...
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21 views

How do you find the number of valence electrons in/draw Lewis structure of a transition metal?

I know that for non-transition metal elements, you just take the column number, but how do you find the number of valence electrons in a transition metal?
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0answers
20 views

IR spectrum of an organometallic compound [closed]

In a solution IR of [CpFe(CO)2]2 (Cp = cyclopentadienyl), 3 peaks are observed. These are: 2006, 1962 and 1794 cm-1. Questions: 1. Why are there 3 peaks (hint: molecular symmetry)? 2. What does each ...
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1answer
39 views

What wavelength of light is released when an electron drops an energy level in complexes?

I know that the color of transition metals is related to the splitting of the d-orbitals. Only a certain wavelength is absorbed in the promotion of electron to a higher d-orbital and therefore the ...
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1answer
45 views

Rate of Fenton Reaction

I want to determine rate of Fenton reaction with different concentration of $\ce{Fe^2+}$. These are some questions that I have encountered: How long does it usually take for the reaction to ...
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0answers
25 views

Trends in the covalency of bonding across the transition metals

I am under the impression that the covalent character in the bonding of transition metal compounds increases across a group; in fact I think this is why they're called transition metals (a transition ...
4
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1answer
70 views

Why can mercury(I) exist, but not zinc(I)?

Mercury shows variable valency while zinc does not. Its electronic configuration is $\ce{[Xe]\:4f^14 5d^10 6s^2}$. So it can donate the $\ce{6s^2}$ electrons and should only be able to form ...
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19 views

Hydrodehalogenation of aryl chlorides

Palladium is the "go to" heterogeneous catalyst for dehalogenating aryl chlorides using hydrogen. What are the chemical (not economic) reasons for other precious metal catalysts not being as common or ...
3
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1answer
79 views

Cr(II) and Mn(III) - their oxidizing and reducing properties?

My textbook states that $\ce{Cr^{2+}}$ is a reducing agent while $\ce{Mn^{3+}}$ is an oxidizing agent in spite of both having $\ce{d^{4}}$ configuration. The explanation states that when ...
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1answer
88 views

What is the chemistry behind black colour of platinum black? [closed]

Platinum is a silvery white metal and is highly unreactive then why it's powdered form "platinum black" is black in colour?
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35 views

Why is Iron (Fe) difficult to reduce?

$\ce{Fe^3+ + e- -> Fe^2+} \quad +0.77$ $\ce{Fe^3+ + 3e- -> Fe} \quad -0.04$ $\ce{Fe^2+ + 2e- -> Fe} \quad -0.41$ $\ce{Zn^2+ + 2e- -> Zn} \quad -0.76$ $\ce{Co^2+ + 2e- -> Co} \quad ...
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63 views

Hiyama vs Sonogashira coupling

Why is Sonogashira's coupling more feasible than Hiyama's coupling when both could occur? I have seen many examples in syntheses, here is one (the penultimate reaction):
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3answers
157 views

How can I understand the Lewis acid-base interaction of iron(III) and water?

The interaction between $\ce{H+}$ and $\ce{NH3}$ as respectively a Lewis acid and a Lewis base is clear for me. $\ce{NH3}$ has a lone electron pair and $\ce{H+}$ has no electrons, or, saying politely, ...
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22 views

Low melting point of Manganeese [duplicate]

Melting point of manganese is lower than that of other 3d series except copper and zinc. Melting point increases from scandium to chromium. The reason given in my book for this trend is the increase ...
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28 views

How do partially protonated sulfate ligands affect a metal's charge?

I'm currently reviewing the Periana-Catalytica system and I have a question about one of the intermediates, namely $\ce{[(bpym)Pt(OSO3H)2]^+}$, which is found in the following tutorial review. How do ...
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2answers
93 views

Method to synthesize KAu(CN)2 (or KCN)?

Every reasonably effective method of electroplating $\ce{Au}$ onto another metal's surface (e.g. $\ce{Cu}$,$\ce{Ni}$,$\ce{Ag}$, etc.) involves use of $\ce{KAu(CN)2}$ or in some cases $\ce{KAu(CN)4}$ ...
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1answer
112 views

Color of Anhydrous Transition Metal Salt

Why are some anhydrous transition metal salts colored? Here are some examples I found. Anhydrous cobalt(II) chloride ($\ce{CoCl2}$), with sky-blue color. Anhydrous chromium(III) chloride ...
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Titrating cobalt II sulfate in a solution with Iron II sulfate

When titrating a solution of iron II sulfate and cobalt II sulfate using EDTA can ammonium flouride be used to mask the iron II in order to quantify the cobalt II without interference?
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400 views

Inner orbital vs outer orbital complex (Tetrahedral vs Square planar)

Restricting our discussions to d block elements and their coordination compounds, Only information given to us is the formula Can you check if these are correct Octahedral (CN=6) If there is a ...
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10 views

Why do some of the transition metals go from 4s2 to 4s1 down the line [duplicate]

I was looking at the periodic table and found for instance that Cu (copper) has an equation of [Ar] 4s1 3d10. Why would this be the case? Why is the 3d orbital filling up completely before the 4s ...
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20 views

Why does stability increase down the 11th Group?

I am quite perplexed by the behaviour of transition metals. Normally I would expect that since atomic radius increases down a group, the ability of the nucleus to retain those valence electrons ...
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1answer
39 views

Questions related to distinguishing dimagnetism and paramagnetism and when is there magnetic properties

If a transition metal ion has both paired and unpaired electrons, would it be considered as showcasing paramagnetism or dimagnetism? I know that Fe2+, which has an abbreviated electronic configuration ...
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188 views

How to calculate denticity of ligands?

When looking at an ligand, how do I know its denticity? For instance, I know that though there are 2 lone pairs in $\ce{H2O}$, its denticity is only 1 due to geometrical reasons as the 2 of them can't ...
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What explains the very high density of osmium and iridium? [duplicate]

Iridium with a density of $22.56$ g cm-3 & osmium with $22.59$ g cm-3. Data from their respective Wikipedia pages. Only these two naturally occurring elements have such a high density. I wish to ...
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1answer
72 views

In crystal field theory, why do all the metal electrons enter the d orbitals and not the s orbital?

Suppose we have the complex $\ce{[Fe(H2O)6]}$. Iron has 26 electrons, and its electronic configuration is therefore $[\ce{Ar}]\,\mathrm{4s^2 3d^6}$, but in crystal-field theory, we say that the ...
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1answer
744 views

Differences between Fe3+ and Fe2+ [closed]

I would like to know the differences between Fe3+ and Fe2+ ions. I'm guessing they must differ in reactivity but I'm not sure how. Also, is there a way that we can observed the differences
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142 views

Why do we say metals are monoatomic in nature?

Are metals monoatomic or polyatomic in nature? For in crystalline form they also form molecular orbitals.
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Why aren't the copper(II) ions in CuSO4 precipitated by hydroxide ions from water?

From my own experience and literature, I know that $\ce{CuSO4}$ is well soluble in water and dissociates into $\ce{Cu^2+}$ and $\ce{SO4^2-}$. $\ce{Cu(OH)2}$, however, is not: $K_\mathrm{sp} = 2 \cdot ...
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Magnetic susceptibility trend

So I was recently looking at this website. http://www.fizika.si/magnetism/MagSusceptibilities.pdf It lists the susceptibility values for inorganic compounds, and I've noticed that the trends don't ...
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Why does some copper (I) compound show color? [duplicate]

As far as I know, if the d orbital of a d-block element is fulfilled, then there is no way for electrons to change the orbital and show color. But some of Copper (I) compounds do show color. How is ...
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Why tungsten does not have stable configuration? [duplicate]

Whenever there are 4 unpaired electrons in d-orbital, elements try to attain stable electronic configuration. For example copper. Electronic configuration of copper should be [Ar]3d4 4s2, but it ...
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2answers
296 views

How can titanium burn in nitrogen?

I was going through the properties of titanium when a certain thing caught my eye: It was the reaction of burning of titanium in nitrogen. I was astonished to read it as I knew that neither is ...
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2answers
106 views

Transition Metal Compounds

So I have a few dumb questions. I'm still in high school and am doing something on magnetic properties of transition metals. I'm facing a few roadblocks. 1) What're compounds like $\ce{CoBr2, CoCl2, ...
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2answers
106 views

Odd Acidity Trend in Hexaaqua Metal Complexes

In the following link (three quarters down the page) it states that theoretically there should be a proportional relationship between the ionic radius and pKa of a hexaaqua metal complex (provided ...
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1answer
227 views

Geometries of 4-coordinate d8 transition metal complexes

The molecule $\ce{[PdCl4]^2-}$ is diamagnetic. Since $\ce{Pd^2+}$ is a $\mathrm{d^8}$ ion, there should be two lone pairs around $\ce{Pd}$. The molecule would therefore belong to the $\ce{AX4E2}$ ...
2
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1answer
80 views

General notation for one of the d-orbitals

What is the general notation to represent the d-orbital with $l=2$, $m_l=0$, i.e. the orbital normally referred to as $\mathrm{d}_{z^2}$. To elaborate more, this orbital can be ordered in various ways ...
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22 views

Reference request for properties of amorphous titanium carbide (a-TiC)

I assume through some side reaction I'm getting $\ce{TiC}$ in my $\ce{TiO2}$ samples after calcination and I need some basic information about the properties of amorphous $\ce{TiC}$. Is it ...
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59 views

Difference in color between the chromate and permanganate ions

As the title states, I'm wondering why the $\ce{[CrO4]^2-}$ and $\ce{[MnO4]-}$ ions display different colors in solution. Both of the metal ions have a $\mathrm{d}^0$ electron configuration, have the ...
5
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1answer
430 views

How can the intense color of potassium permanganate be explained with molecular orbital theory?

In the permanganate ion, manganese is in the $+7$ oxidation state, therefore it is a $\ce{d^0}$ ion. $\ce{d^0}$ and $\ce{d^1^0}$ ions don't absorb visible spectrum radiation because there are no ...
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1answer
164 views

What is the lattice structure of manganese?

A transition element is defined as the one which has incompletely filled d orbital in its ground state or in any one of its oxidation state. Zinc , cadmium and mercury are not typical transition ...
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2answers
2k views

How many valence electrons do elements in the d block have?

I just noticed that on the periodic table it doesn't say how many valence electrons there are for each column in the d block. How do I find out how many valence electrons elements in the d block ...
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1answer
57 views

Making elemental sulfur from pyrite FeS2

Has anyone done this or know of a good experiment that would allow someone to make elemental sulfur from $\ce{FeS2}$ (iron pyrite)?