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].
399
questions
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2answers
154 views
How is Zn not a transition metal? [duplicate]
A transition metal can be defined as an element that possesses an incomplete sub-level in one or more of its oxidization states. In the textbook I'm reading, it claims that zinc is not a transition ...
2
votes
1answer
65 views
What happens when ferric chloride is dissolved in water?
Ferric chloride can be prepared by dissolving hematite in hydrochloric acid:
$$\ce{Fe2O3 + 6HCl -> 2FeCl3 + 3H2O }\tag{1}$$
But the resulting ferric chloride will be exposed from its formation to ...
4
votes
2answers
288 views
Chromium cyanide complexes
I have rarely seen any chromium $(\ce{Cr})$ square planar complexes and I have been told that $\ce{[Cr(CN)4]-}$ is tetrahedral.
So, if the statement is actually correct, are there any other known ...
1
vote
1answer
53 views
When disolving a iron pill for titration, why do I use sulfuric acid instead of nitric or hydrochloric acid?
In a titration to decide the iron content of a pill we dissolved the iron in sulfuric acid and then titrated it with cerium(IV) sulfate. But I just wondered what's wrong with using nitric and ...
8
votes
1answer
64 views
Should we expect Jahn–Teller distortion in bis(ethylenediamine)nickel(II)?
(ii) The stepwise stability constants of the following complexes in aqueous solution at $\pu{25 °C}$ are given below:
$$
\begin{array}{cll}
\hline
\ce{M} & \ce{[M(en)2(H2O)2]^2+} & \ce{[M(...
1
vote
0answers
25 views
Stability order of chelate complexes of nickel and iron
Which stability order is correct?
$\ce{[Ni(en)2]^2+} > \ce{[Ni(dmg)2]}$
$\ce{[Fe(edta)]^2-} > \ce{[Fe(en)3]^3+}$
In the first case I think the stability depends upon the strength ...
1
vote
1answer
50 views
Can oxygen gas in air react with Mn3O4 to form MnO2?
I think $\ce{MnO2}$ at high temperature can be used as a catalyst for $\ce{SO2 + O2 -> SO3}$:
$$
\begin{align}
\ce{MnO2 + SO2 &-> MnSO4}\tag{1}\\
\ce{3 MnSO4 &-> Mn3O4 + SO2 + 2 SO3}\...
1
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3answers
60 views
Which would have a more intense transition: a low spin d6 complex or a high spin d5 complex?
I have an assignment question for second year inorganic which asks to rank the intensity of d-d transitions for a number of complexes. Two are $\ce{[Fe(OH2)6]^3+}$ and $\ce{[Fe(CN)6]^4-}.$ Both will ...
1
vote
0answers
21 views
Separation of Noble Metals for scrap recovery
I am researching scrap metal recovery as a side job and am hitting a wall with the noble metals. Gold, Silver, Platinum, and Palladium seem like they're all fairly easy to recover. I just can't find a ...
0
votes
1answer
61 views
Isolating barium(II), copper(II) and zinc(II) from aqueous solution [closed]
Q15 Each metallic ion was separated from an aqueous solution containing $\ce{Ba^2+},$ $\ce{Cu^2+},$ and $\ce{Zn^2+}$ by the procedure shown in the following figure. From ①–⑥ in the table below choose ...
-2
votes
1answer
64 views
Conditions for the reduction of dichromate by manganese(II) to chromium(III) [closed]
The unbalanced redox reaction
$$\ce{Mn^2+ + Cr2O7^2- -> Mn^3+ + Cr^3+}$$
occurs in what type of condition?
(a) Acidic
(b) Basic
(c) Neutral
(d) Indeterminable
2
votes
1answer
58 views
Why does the displacement reaction of zinc in copper(II) sulfate solution result in dark metallic copper?
It is commonly known that when zinc metal is placed in a solution of copper(II) sulfate, a displacement reaction occurs, and elemental copper is deposited onto the decomposing zinc metal. A practical ...
-2
votes
1answer
72 views
Can concentrated sulfuric acid oxidize iron(II) to iron(III)?
Can concentrated (18 M) $\ce{H2SO4}$ oxidize $\ce{Fe^2+}$ to $\ce{Fe^3+}?$ Or does it actually block the oxidation? I read in some forum somewhere that in order to prevent $\ce{Fe^2+}$ from being ...
-1
votes
1answer
42 views
Cupric and cuprous copper [duplicate]
Copper has two chlorides: $\ce{CuCl2}$ and $\ce{CuCl}.$
Copper reacts directly with chlorine to form a copper(II) chloride. Why doesn't it form copper(I) chloride? Is it because $\ce{CuCl2}$ is more ...
-2
votes
2answers
59 views
How to know dichromate is being reduced from Cr⁶⁺ to Cr³⁺?
When potassium dichromate is being used as an oxidising agent, it gets reduced from chromium(VI) to chromium(III). Is there any way to know that or calculate that other than being familiar with ...
0
votes
1answer
344 views
What is the hybridization of chromium in chromate and dichromate ions?
I was recently reading about the transition metals and some important compounds of them. I came across a rather interesting diagram in my book... a tetrahedral structure for the chromate ion. The only ...
1
vote
1answer
44 views
CO-vibration in metal carbonyl
I'm struggling to understand the trend of $\ce{CO}$-vibration in isoelectronic metal carbonyls.
$$
\begin{array}{lr|lr}
\hline
\text{Compound} & ν/\pu{cm-1} & \text{Compound} & ν/\pu{cm-1}...
5
votes
1answer
209 views
Is scandium considered a transition metal?
I have seen so many conflicting answers to this question in various places so I wanted to ask it again.
IUPAC defines a transition element as
an element whose atom has a partially filled d sub-...
1
vote
2answers
126 views
Synthesis of potassium trioxalatocobaltate(III) trihydrate
I've synthesized the compound potassium trioxalatocobaltate(III) trihydrate and for it I have two reaction equations. One of them is:
$$\ce{CoCO3 + 3K2C2O4.2H2O -> K2[Co(C2O4)3] + 2CO2}$$
and the ...
16
votes
1answer
807 views
What is the oxidation state of Mn in HMn(CO)5?
What is the oxidation state of $\ce{Mn}$ in $\ce{HMn(CO)5}$? If $\ce{H}$ has an oxidation state of $+1$, then $\ce{Mn}$ should have oxidation state of $-1$, which I'm not sure is possible.
On the ...
2
votes
0answers
82 views
Explain why can't zinc be plated out from a Zn(II) solution using standard reduction potentials
I am currently learning about electrochemistry using Zumdahl's Chemistry [1, pp. 709–710]. One of the critical thinking questions is
Why can $\ce{Zn}$ not be plated out from an aqueous solution of $...
1
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0answers
24 views
Nature of the bonding in hexaaquaaluminium complex
$\ce {[Al(H2O)6]^3+}$ is a well-known complex ion formed by the $\ce {Al^3+}$. I have always had the understanding that only the aqua complexes of transition metal ions, such as $\ce {[Fe(H2O)6]^3+}$, ...
0
votes
0answers
66 views
Why decanted solution should be colorless when determining formula of unknown chloride?
I was following the guide “Stoichiometric Determination:
Empirical Formula of Copper Chloride”.
Under the Procedure section the following reaction is given:
Producing solid $\ce{Cu}$ from a $\ce{Cu(...
1
vote
0answers
45 views
Factors that influence the electrical conductivity of metals
The electrical conductivity of metals is a physical property of these materials. Much of the theory used to explain the electrical conductivity of metals is also based on physics understanding. ...
7
votes
0answers
85 views
Does tantalum and tungsten really not form amalgams?
User @Poutnik has recently answered two questions(here and here) in which he/she quoted this statement from Wikipedia:
Almost all metals can form amalgams with mercury, the notable
exceptions ...
0
votes
1answer
92 views
Molar conductivity of transition metal complexes solutions [closed]
Which of the following has the highest molar conductivity?
(A) Diaminedichloroplatinum(I)
(B) Tetraamminedichlorocobalt(III) chloride
(C) Potassium hexacyanoferrate(II)
(D) Hexaaquochromium(...
0
votes
0answers
26 views
Oxidation of Hexaaquachrom (II) with air
I had the reaction:
$$\ce{Cr(H2O)6^3+ -> Cr(H2O)6^2+}$$
using $\ce{Zn}$ as a reducing agent.
the colour turning from green to blue and I know that with contact with air the solution becomes ...
2
votes
2answers
82 views
Colour of metal complexes with the same type and number of ligands
Crystal Field Theory says that because of d-orbital splitting caused by different ligands we have 2 different energy levels for d-orbitals.
It also says that transition metals are coloured because ...
1
vote
1answer
231 views
Products of the reaction between chromium(III) chloride, zinc and sulfuric acid
The aim of my experiment was to make a Cr(II) aquacomplex in situ, and for that I have the reaction:
$$\ce{CrCl3·6H2O + Zn}$$
and I add concentrated sulfuric acid to it. I know that chromium(III) ...
1
vote
0answers
37 views
What chemical reaction could be used to make copper pennies a vibrant red?
I’m an artist working on a piece using pennies to illustrate my drawing and I need my pennies to be red in a certain portion. I’m trying not to use paint and was wondering if there was a way to make ...
-1
votes
1answer
59 views
Reaction of coloured metal complexes with water and sulfuric acid [closed]
Reaction of coloured metal complexes with water and sulfuric acid
I recently started researching the coloured compounds made from transition metals focusing on one with oxidation state II, so Mn,Fe,...
2
votes
1answer
90 views
Mixing cobalt(III) hydroxide and thallium(III) hydroxide
A simple question on solutions is driving me crazy. At this point, I think the textbook's wrong. Here's the question:
A saturated solution of cobalt(III) hydroxide $(K_\mathrm{sp} = \pu{1.6e-44})$ ...
1
vote
0answers
402 views
Definition of early vs. late transition metal
Is there an accepted definition of an early or late transition metal? I think the late transition metals start at Group 8 (including Fe), but others have said Fe is not a late transition metal. I'm ...
8
votes
2answers
1k views
Why is Ni[(PPh₃)₂Cl₂] tetrahedral?
Since PPh₃ is strong field ligand and, the famous Wilkinson's catalyst, which also possess this ligand is square planar, then what makes the above complex tetrahedral?
10
votes
1answer
203 views
Why are palladium and platinum carbonyls unstable at room temperature?
By palladium and platinum carbonyls, I mean the mononuclear, homoleptic, charge-neutral, binary carbonyl complexes of the form $\ce{M(CO)_n}$ and not any heteroleptic complexes like $\ce{Pd(CO)(PPh3)3}...
7
votes
1answer
97 views
Reference for electronegativities of different metal oxidation states
A long time ago I was researching the effect of the self regulatory response in Fe and Co. I found that my results made sense based on the idea of the electronegativity of the ions considered. I found ...
1
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0answers
88 views
Why do tetrahedral organic molecules show stereo-isomerism, but not tetrahedral transition metal complexes?
Both types of molecules show different arrangements of the molecule in space, so they should qualify for optical isomerism right?
1
vote
1answer
220 views
Why do some ions form tetrahedral complexes more readily than others? [closed]
Why does Co$^{2+}$ readily form tetrahedral complexes such as [CoCl$_4$]$^{2-}$, whereas Fe$^{2+}$ usually forms octahedral complexes?
7
votes
1answer
368 views
Only d orbital electrons for spin only magnetic moment
During my chemistry lessons and self studies, I have come upon many instances where I observed that during calculations of spin only magnetic moment of transition elements only the d orbital electrons ...
0
votes
1answer
51 views
Why is the reason for color different in these two cases? [closed]
I have read in a book (NCERT India) about flame color for salts of alkali metal and color of transition metal complexes.
In the first case, it says that during excitation of electrons to higher ...
0
votes
0answers
149 views
Why does copper jewelry & wire smell bad - even when I'm not wearing it?
I make jewelry by weaving a frame from copper wire for a gemstone, then making copper coils or spirals, etc for further decoration. Even 'on the roll', the copper wire smells bad - and the smell ...
0
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0answers
27 views
Why do heavier d block elements are more stable in higher oxidation states than lighter d block elements? [duplicate]
I read that it is because it is easier to ionise the elements as the electrons involved are those of d orbitals which have same degeneracy. First of all, i found it very vague. Secondly, what about ...
2
votes
0answers
36 views
Reactivity of Ni Vs. Pd - available oxidation states
I'm hoping someone can help me tighten up my understanding of the origins of the differences between Ni and Pd catalysis.
I understand that Ni has higher charge density and this is the reason for it'...
1
vote
0answers
36 views
Metal complexes and bonding of ligands
I am currently learning about transition metal complexes, however I keep seeing complexes like $\ce{[Al(H2O)6}]^{3+}$ but aluminium isn't a transition metal. Is this a case that any metal can form a ...
2
votes
2answers
245 views
Colour change when excess ammonia added to [Cu(H2O)6]2+
Since ammonia is a stronger ligand than $\ce{H2O}$ shouldn't the colour of the new solution $\ce{[Cu(NH3)4(H2O)2]}$ be lighter as the energy gap will be higher and so light with higher frequency and ...
2
votes
1answer
750 views
How to determine the greatest d orbital splitting?
This question comes specifically from an IB Chemistry HL Paper 1 in May 2018 TZ1, namely question 8.
Which complex has the greatest d orbital splitting?
It gives 4 Complexes $\ce{[Fe(H_2O)_6]^{2+}}$,...
2
votes
0answers
17 views
Metal catalysts used in C-H bond functionalisation [closed]
Why are the late transition metals used for C-H bond activation/functionalisation? What atomic properties of the late TM make them attractive for coordinating C-H sigma bonds?
Thanks.
1
vote
1answer
56 views
How to convert soluble colorless [HgI₄]²⁻ back to insoluble red HgI₂? [closed]
When a solution contains $\ce{Hg^2+}$ and $\ce{I-}$, depend on the concentration ratio of $\ce{Hg^2+}$ and $\ce{I-}$, the following reactions can happen:
$$\ce{Hg^2+ + 2 I- ⟶ \underset{insoluble red ...
0
votes
0answers
98 views
ML6 Type Coordinate Complexes - Drawing a Molecular Energy Orbital Diagram
In class we recently discussed how to draw out molecular orbital energy diagrams for compounds such as NH3 (ammonia). Building upon this, we touched on how to construct a molecular energy diagram for ...
1
vote
0answers
85 views
Qualitative analysis of iron(III) salt
Why will $\ce{Fe^3+}$ give brown ring test?
In my textbook it was given that ferric ion gives brown ring too. I am confused, if ferric ion is already present, then what will reduce nitrate ion to ...
