Questions regarding elements between Group 3 and Group 12 (inclusive), or also referred to as d-block.

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What makes a ligand stronger than another?

A ligand is a neutral molecule or negative ion with at least one lone pair of electrons which forms a dative covalent bond with a complex ion that has a vacant, energetically accessible orbital. It ...
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1answer
33 views

Explanation for increase in the number of oxidation states for transition elements from Sc to Mn of the 4th period

From Sc, to Mn, the number of oxidation states increases from one (Sc) to seven (Mn). The explanation for this is because the unpaired 3d electrons can be lost along with the 4s electrons during ...
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2answers
30 views

Transition metal order of filling electron

There is a specific order for filling electron for transition metals, but I don't know if it applies to other elements too? Some thing to take note of in this picture is the order of 3d and 4s. My ...
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1answer
44 views

Valence Shell for Transition Metals

In transition metals, is the shell with the highest energy considered the valence shell? For example, in copper the electronic configuration is ${[Ar]\text{ } 3d^{10}\text{ } 4s^{1}}$. However, in ...
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26 views

Why is Technetium unstable?

Technetium is probably the most awkward element of the periodic table for me. It seems to me that Technetium is an exception, in the sense that it doesn't have any stable isotopes, despite having a ...
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32 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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53 views

Stability of transition metals in aqueous solution

Which is more stable in aqueous solution $\ce{Cr^{3+}}$ or $\ce{Mn^{3+}}$? And why? My approach: $\ce{Cr^{3+}}$ should be more stable as the 3d electrons will enter the $t_{2g}$ orbitals. Due to CFSE ...
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0answers
21 views

Spectrochemical Series - Sigma Donor Capability

I fully understand and recognise the manner and which the series works. I cannot find any references for the change in sigma donor capability moving up the series. For example, comparing Cl- and ...
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1answer
41 views

Crystal Field Theory diagram

I need to draw a simple crystal field splitting diagram and identify the lowest-energy spin-allowed ligand field band in the electronic absorption spectrum for [MnCl6]2-. I know the basics of the ...
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1answer
57 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
219 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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3answers
434 views

what is the origin of the colour of azo dyes?

what is the origin of the colour of azo-dyes? Is it the same reason as to why transition metal complexes have colour?
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1answer
60 views

Why Gold and Silver react minimally with atmosphere?

Gold and Silver atoms interact with one another to form reasonably strong metallic bonds, but surprisingly they have almost no chemical interaction with atmosphere. How can we explain it based on the ...
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Why does $\text{Cr}^{3+}$ not have the same electron configuration as $\text{Sc}$?

To be explicit, $\text{Cr}^{3+}$ and $\text{Sc}$ have the same number of electrons, the only difference is the nuclear charge. This is not an isolated anomaly, it seems: the book I'm using claim ...
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2answers
109 views

Problems with precipitation of transition metal solution

I am trying to make a solution of "trace elements"--primarily transition metals-- for use in biological media; bacteria require elements like Cobalt, Molybdenum, iron, etc. in trace amounts. I am not ...
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1answer
151 views

Is pyrite (FeS2) an ionic or a covalent compound?

I have searched all over the web and found a lot of diverse explanations, but none of them are concluding exactly whether $\ce{FeS2}$ (solid - pyrite) is a covalent or an ionic compound. From ...
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3answers
138 views

Can we goldify metals?

I've read in some book that one of the old chemists was able to transform cheap metals into gold. I know that gold is an element (Au) so we can't transform a metal into Au. But as I read further it ...
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1answer
133 views

Variable oxidation state of transition metal ions

Transition metals can form stable ions with different oxidation states. But I am confused why doesn't only the most stable state exist. Let me clarify my question more: $$\ce{Ti^{2+} -> Ti^{3+} + ...
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33 views

About Ti and Nb size [duplicate]

I am confused about the atomic size of transition elements. Why are titanium and niobium similar in size?
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66 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
170 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 ...
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1answer
77 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 ...
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1answer
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Why can we smell copper?

If I can smell an object, it means that molecules of it are getting separated from it, so they can reach my nose. As far as I know, metals don't sublimate, especially not in room temperature. However, ...
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0answers
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Do these compounds Na$_x$IrO$_2$ and NaOsO$_2$ exist?

Based on some physics background, I want to know whether have we synthesized these two materials: $\ce{Na_{x}IrO2}$ and $\ce{NaOsO2}$ in the lab, if so, what properties do they have? I will be very ...
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Bond Lengths in FCC, BCC and HCP Structures

I was wondering what the crystal structures of FCC, BCC and HCP actually look like, and where atoms are placed in their configuration? Specifically I'm looking at elemental nickel, iron and cobalt ...
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Will Mg(II) or Fe(III) be more active in Catechol-O-methyltransferase? [closed]

There is an enzyme called COMT that catalyses this reaction: where SAM is a cofactor and M is a metal atom. In case ...
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1answer
282 views

Calculating percentages of microstructures in equilibrium phase diagrams (engineering)

So I have an equilibrium phase diagram of steel and I am asked to 'Calculate the proportion of pearlite in the microstructure of 0.4 wt% C steel just below the eutectoid temperature (727 °C).' I have ...
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1answer
215 views

Co-ordination compound [Co(SCN)4]2-

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

Chelation and its relation to transition metal ligands

Can someone explain chelation and its relation to monodentate and tridentate ligands? I dont understand what they mean by chelate effect and chelating rings.
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124 views

How can silver work as a disinfectant in a bathtub if precipitates in the presence of chloride?

I use a silver based disinfectant in my hot tub. It is in the form of silver nitrate beads. There is chlorine in the tub that I presume becomes chloride ion. Why doesn't the silver form a precipitate ...
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1answer
449 views

How do I determine the crystal field splitting for an arbitrary point group?

How can I figure out the degeneracy of the d orbitals for a site that has a given point group? Specifically I'm interested in $D_{3d}$ and $D_{3h}$, but it would be good to know how to do it in the ...
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1answer
83 views

Transition Metals' Charges

I came across a compound $\ce{[FeO4]^{2-}}$ but $\ce{Fe}$ has +6 charge according to my calculations. How this is possible ? Or it is possible but my periodic table is kind of non-detailed one. (On ...
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1answer
89 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, ...
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1answer
218 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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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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2answers
4k views

Why are some salt solutions coloured?

I notice that salt solutions of $\ce{NaCl}$ and $\ce{KCl}$ are colourless while those of $\ce{CuSO4}$ and $\ce{FeSO4}$ are coloured. I got as far as figuring that it has to do with the transition ...
5
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1answer
165 views

Brittle d-block metal trend

I remember seeing a periodic table that had the top-left corner of the d-block shaded and marked as "brittle". If I recall correctly, the elements were $\ce{Sc,Ti,V,Cr,Mn,Y,Zr,Nb,La}$. I think (Sorry, ...
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5answers
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Why do elements in columns 6 and 11 assume 'abnormal' electron configurations?

When I look around for why copper and chromium only have one electron in their outermost s orbital and 5/10 in their outermost d orbital, I'm bombarded with the fact that they are more stable with a ...
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2answers
7k views

How is Vanadium's 3+ ion paramagnetic?

"Both Vanadium and its 3+ ion are paramagnetic. Use electron configuration to explain why this is so" The electron configuration of Vanadium is [Ar] 4s2 3d3. If drawn in a box diagram, it would ...