Questions tagged [transition-metals]
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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Effect on Metal-Phosphine Bond if Metal centre gets oxidised
Looking at the Octahedral complex, the chromium is a $d^6$ complex and, if the Chromium bond gets oxidised, it will have lesser electrons to donate to phosphine's $\sigma^{*}$ orbital.
This effect is ...
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Why does the answer given consider octahedral splitting even though there is no specification of the complex
My textbook (NCERT Chemistry Part 1) gives this question as an example:
Why is $\ce{Cr^2+}$ reducing and $\ce{Mn^3+}$ oxidising when both have $d^4$ configuration?
And the solution given along with ...
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Deriving population of $t_{2g}$ orbitals in transition metal oxides
I have recently studied ligand field theory but there is one thing I do not understand.
Consider an octaedral geometry of ligands around a transition metal with a $t_{2g}$ - $e_g$ splitting of atomic $...
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Can someone help with GAMESS input files for heavy atom calculations (MoS2, WS2, etc.)?
I'm doing computational research on transition metal dichalcogenides for my chemistry class and I want to calculate a transition state optimization for the reaction $\ce{MoS2 +N^- -> MoSN + S^-}$. ...
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Why don't Zn, Cd, Mn and Hg have more than one metallic structure at normal temperature, while other d-block elements do?
It's been given in my book, that "With the exceptions of Zn,
Cd, Hg and Mn, they have one or more typical metallic structures at
normal temperatures."
But, why this exception?
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What's the reason of curvature in Tanabe-Sugano diagrams?
Analysing Tanabe-Sugano diagrams it's evident that some of the lines are pretty parallels to that of the ground field whilst others are inclinated or have some curvature.
I know what's the effect on ...
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Do the paired electrons of subshells' degenerate orbitals contribute to the total exchange energy?
For instance, in d7, there are 5 electrons with the same spin, and 2 electron with the opposite spin, meaning that there are only 3 unpaired electrons. So, which of these would be correct?
(i) Total ...
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Why is iron(III) more stable than iron(II)?
What I have seen, and what has been answered before (Why Fe 3+ is more common than Fe 2+), is that it is due to the half filled d orbital of $\ce{Fe^3+}$ compared to $\ce{Fe^2+}$. I don't understand ...
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What is happening in experiment coating a copper coin with zinc and turning it to brass?
Today in class we did the "gold penny" experiment, where we put metallic zinc and a penny in a zinc chloride $\pu{1 M}$ solution at $\pu{100 °C}$, which caused the penny to turn silver as ...
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What is the oxidation state of atoms in interstitial transition compounds?
My teacher said that even though interstitial compounds are neither ionic nor covalent, we still define an oxidation state for them. The example she gave was $\ce{TiC}$. She said the carbon is in $-4$ ...
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If gold does not oxidise in air, why doesn't it reform it's lattice?
It is a common fact that without oxidation, a metal can reform it's lattice with a tad bit of pressure.
Gold is often said to be non-oxidising(doesn't oxidise in ambient temperature and pressure) and ...
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Why does Cr have higher melting point in the 4 period among the transition metal? [duplicate]
There is a lot of answer stating that the low enthalpy of atomisation in Cr is due to the reason of partially filled d orbital, thus having extra stability. This makes the orbital more attracted ...
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Crystal Field Splitting for a d0 metal ion
Its well-known that crystal field splitting occurs because the electrons in d orbitals repel incoming ligands and the d orbitals are no longer degenerate.
My question is now: is the repulsion (with ...
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What is the shape of tetraamminenickel(II) complex?
I have basic knowledge of crystal field theory (CFT) and how to predict geometries in complexes with a coordination number of 4.
For $\ce{[Ni(NH3)4]^2+}$, we find that the metal center, $\ce{Ni^2+}$, ...
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1
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Significance of Character tables in d orbital splitting
When we have a molecule say (Co(NH2)6) hypothetically any octahedral molecule it has the point group of Oh and the character table shows the quadratic function such as ($z^2,2z^2-x^2-y^2$) ($xy, xz, ...
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The electron structure in transition metallic bonding [duplicate]
Copper has an electron structure of $\ce{[Ar] 3d^10 4s^1}$. In salts it may form two stable ions, the $\ce{Cu^+}$ and $\ce{Cu^2+}$. (It's actually not very clear to me why the 2+ ion is common, why ...
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Trend in formation enthalpy of metal fluorides
Please see below for the data I am referring to. I don't really understand why the trend in Cr ceases and reverses.
I think I understand what the logic for WFn is - while the cost of forming Mn+ ...
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Why do the successive ionisation energies of Ni and Pt diverge?
The data I am referring to is below on the graph. The explanation I have found is that the 5d orbital of Pt is more diffuse than the 3d orbital of Ni, so is less sensitive to the increases in Zeff as ...
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Theoretical explanation for: Why is KMnO4 stronger oxidizing agent than K2Cr2O7?
I know that it can be explained using the Reduction Potential values. But, can it be explained from their structures or something like that ?
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Can I convert copper(II) acetate or carbonate to copper(II) sulfate?
I am a high school student who does chemistry as a hobby, and as such I really don't know very much. I managed to make some copper(II) acetate and copper(II) carbonate, and now I'd like to convert it ...
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Why do Mn and Tc have lower melting points with respect to their immediate neighbors but Re doesn't?
Manganese (Mn) and technetium (Tc) show a sharp decline in their melting point in comparison to the neighboring transition elements, which is unexpected while following the general trend which says ...
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Creating resilient (non-brittle non-water-soluble) verdigris (blue-green copper patina)
First off, I checked and there are indeed a number of questions on copper patinas, but none which deal with resilience.
Context
I own a number of copper writing utensils, which I'd like to get a nice ...
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How to get Raman shift frequency values from neutron scattering measurements?
I have read some papers that say that a Kohn anomaly mode is a particular feature of 2H- transition metal dichalcogenides and that the existence of such a mode can be seen in neutron scattering data ...
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Lower melting points of zinc, cadmium and mercury
I am aware of the fact that d-block elements like zinc, cadmium and mercury have lower melting points than other d-block elements. Also I am aware that these three metals have a fully filled d shell.
...
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Nichrome alloy corrosion at high temperature
We are currently using a nichrome (80/20) wire based heater to surround a sample chamber that we wish to heat by radiation. Maximum sample temperature is 400degC in an atmosphere of air that may be ...
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Why middle elements of transition series show more number of oxidation states [duplicate]
Why do the elements in the middle of the transition series show more number of common oxidation states than others?
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Why is nickel anticorrosive?
I've been looking into corrosion and common ways to prevent it. Pure nickel seems to be the main anticorrosive material to use, but I can't find a decent answer as to what it has/does that other ...
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Why does berkelium have two electronic configurations?
J.D. Lee Concise Inorganic Chemistry, Appendix E: Electronic Structures of the Elements [1, p. 601] provides two electronic configurations for berkelium:
$$
\ce{Bk}\quad
\begin{cases}
[\ce{Rn}]~\...
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How many multivalent elements are there? [closed]
According to this video there are 20 multivalent elements, and from the periodic table, I see 20, but according to multiple websites, including this, it says there are only 5. What am I not ...
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Store Palladium Chloride in Solution
I have one gram of palladium chloride ($\ce{PdCl2}$) and I want to use very small quantities of it, in milligrams somewhere. It is not possible for me to get my hands on a scale that can measure that ...
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How do we know the ionic charge of iron or elements such as iron on the periodic table?
How do we find iron's ionic charge? I was taught that we use roman numerals but I don't see any on the basic periodic table of elements (I'm using this one). So how do we find iron's charge of Fe 2+ ...
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How long does it take for zinc oxide powder and heinz vinegar to fully react into zinc acetate at a 1:2 ratio of zinc:heinz vinegar? [closed]
How long should I leave a solution of zinc oxide powder and heinz vinegar in order for it to react as completely as possible? The solution is 1(zinc oxide powder):2(heinz vinegar) in a glass flask. ...
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Can you oxidize gold using only oxygen?
I keep reading that gold does not react with oxygen, but I also see information about gold Oxides (ie: aurous oxide, Au2O and auric oxide, Au2O3)
Knowing that there is a way of getting gold oxide ...
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Why is AgOH brown when silver(I) ions are colorless?
As Wikipedia states, $\ce{Ag+}$ ions are colorless in solution: https://en.wikipedia.org/wiki/Color_of_chemicals
Compounds that I know of containing $\ce{OH-}$ are also colorless or white (such as $\...
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Is hydrochloric acid or sulfuric acid more corrosive to titanium?
Which acid is more corrosive to titanium at 20 to 30 °C and similar concentrations: hydrochloric acid $\ce{HCl}$ or sulfuric acid $\ce{H2SO4}$?
I found some info on AZoMaterials — Titanium - Corrosion ...
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Does chromium(III) oxide react with or dissolve in liquid sulfur dioxide?
Liquid $\ce{SO2}$ (b.p. −10 °C) is known as a versatile solvent (yet not particularly pleasant to work with) for a wide range of organic and inorganic compounds having limited solubility in ...
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How to safely alloy magnesium castings into aluminum?
I want to dissolve previously sand cast magnesium to molten aluminum to create an aluminum magnesium alloy. Of course I want to do this as safely, and inexpensively, as possible. I have an electric (...
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Is hydroxylamine monodentate or ambidentate ligand?
What is the total number of geometric isomers of the complex $\ce{[Pt(Cl)(py)(NH3)(NH2OH)]+}$?
If $\ce{NH2OH}$ acts as an ambidentate ligand, then there should be six geometric isomers. Or is it ...
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Can proton NMR be used to study transition metal complexes?
I prepared metal complexes with a Schiff base ligand L using cobalt(II) chloride hexahydrate, iron(III) chloride hexahydrate, and nickel(II) nitrate hexahydrate. I used 1H NMR to study the difference ...
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What are oxidation numbers of each element in CuH?
My chemistry teacher said hydrogen when bonded with metals has oxidation number (O.N.) of −1 except CuH: in CuH the hydrogen has O.N. +1 and the copper has O.N. −1.
But on the internet it is ...
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Evaporation of zinc oxide
My question involves the evaporation of silicate material (e.g., rocks, minerals, geologic material), specifically I am trying to work the number of electrons (n) that are involved in the evaporation ...
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Does solid manganese reacts with atmospheric air when heated?
As discussed in my answer, manganese is not particularly reactive to air. The surface of manganese lumps oxidize to a minor extent but when it is finely divided, it becomes pyrophoric and burns in air....
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How do you determine the charge of the metal ion in a single replacement reaction? [closed]
Say we have a simple single replacement reaction between a salt and a metal
$$\ce{2 AgNO3 + Cu -> Cu(NO3)2 + 2 Ag}$$
We know in normal circumstances, silver always has a $+1$ charge, and in normal ...
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Electrolysis when E_cell = 0
I'm a bit confused by the electroplating of Zinc onto Copper, with Zinc (anode) and Copper (cathode) electrodes in a Zn(NO3)2 solution.
The reduction reaction is: Zn2+ + 2e- ---> Zn (s) (E_rxn = -0....
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Displacement Reaction [closed]
In a displacement reaction I understand that the more reactive metal essentially takes the place of the less reactive metal. But I can't seem to understand how this more reactive metal can break the ...
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Relative stability of $\ce{V^2+}$ and $\ce{V^3+}$ and their Standard Electrode Potential
My book - NCERT Chemistry for Class XII -Page 218 Contains the following paragraph:
Initially they mention that the Low value for Standard Electrode Potential of $\ce{Sc^3+/Sc^2+}$ is due to the ...
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Determining iron(III) content in mixture of iron(II) and iron(III) [closed]
Problem
Outline a plan of an experiment to determine the percentage of iron present as iron(III) in a solution containing $\ce{Fe^3+(aq)}$ and $\ce{Fe^2+(aq)}$ ions. You are provided with zinc, a ...
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Melting and boiling point of transition-metals, primarily for the groups of Cr and Mn [duplicate]
The NCERT Chemistry book for Grade 12 writes
The high melting points of these metals are attributed to the involvement of greater number of electrons from $(n-1)d$ in addition to the ns electrons in ...
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Why does low spin character predominate in hexafluoronickelate(IV)?
According to my book there are no unpaired electrons in $\ce{NiF6^2-}$. However, that should not be the case since fluoride is a weak field ligand. Why does hexafluoronickelate(IV) behave as a low ...
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1
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Atomic Radius of Manganese and Chromium
It is clearly a general trend that the atomic radii of the 3d elements in ascending order of atomic weight, leads to the following trend as in the graph below.
But, it was pointed out to me that, Mn ...
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