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

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Why does Manganese have so many stable oxidation states? [on hold]

Manganese ions are stable at various oxidation numbers, going from -3 to +7. Why?
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29 views

Why doesn't the bidentate ligand form dative bonding three times?

I was looking at this question where it asked you to work out the final complex formed when an excess of 1,2-diaminoethane is added to and aqueous solution of copper (II) sulphate. So the equation I ...
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1answer
22 views

Transition Metals colours and electron absorbtion

I understand that when d-orbitals split some electrons can occupy the higher orbitals by absorbing frequencies of light, but do these electrons then fall back to their original ground states? If so, ...
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22 views

What happens to the colour of a transitional compounds when an electron is excited by visible light? [on hold]

I know that when the electron is excited, it goes to a higher energy level and then when it comes back down, the light is reflected/transmitted with a different colour. So when the electron does ...
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27 views

Why would a reaction take place in this instance?

This makes little sense to me, both of the electron configurations are d6, and would presumably be low spin - therefore both reactants should be inert, and yet my notes suggest that an electron ...
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1answer
20 views

Ions of transition metals

Why Chromium tends to form Chromium 3+ ion?Is it because it is stable? If yes,i don't understand why because its d orbital is filled with 3 electrons only,it is not a noble gas configuration.Can ...
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1answer
59 views

How to determine the magnetic character of heteroleptic complexes?

I was asked to find out the magnetic behavior (and essentially electronic configuration) of heteroleptic complexes using Valence Bond Theory and Crystal Field Theory. But I am confused about how to ...
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48 views

Can oxidation of ethanol by copper(II) oxide yield copper(I) oxide as one of the products?

We know that ethanol is oxidised by copper(II) oxide to an aldehyde. Copper is reduced from $\ce{Cu^2+}$ to $\ce{Cu}$. Can this reaction, with some specific condition, yield $\ce{Cu2O}$ instead? That ...
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2answers
419 views

Why is manganese(II) coloured although the transition should be spin-forbidden?

In every basic coordination chemistry class, at some early point the crystal field theory and LFSE will be taught, explaining that there will be an energy difference between d-orbitals (typically ...
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1answer
51 views

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 ...
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1answer
58 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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10 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
93 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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45 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
80 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
41 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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22 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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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
47 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
51 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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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 ...
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1answer
75 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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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 ...
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1answer
88 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
96 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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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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65 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
170 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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0answers
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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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30 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
106 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
148 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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575 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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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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23 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
50 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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246 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
78 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
2k 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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165 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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214 views

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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353 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
109 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, ...