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].
415
questions
0
votes
1answer
62 views
How to precipitate Chloroplatinic acid?
For the precipitation reaction, I have to react $\ce{H2PtCl6}$ with $\ce{(NH4)2CO3}$ while maintaining the $\ce{pH}$ in the range of 7-8 at 60 °C. But the problem is Chloroplatinic acid is not ...
-4
votes
1answer
20 views
Why n-Butane has high B. p than iso-Pentane although both have equal no. of carbon atoms along the chain length? [closed]
n-Butane =B. p =-1 oC
iso pentane =b. p= 28 oC
-1
votes
0answers
50 views
Why are group 7 to 9 elements good hydrogenation catalyst?
In my exam question came: statement 1- activity of hydrogenation catalyst increase from group 5 to 11 with maximum activity shown by group 7 to 9 group elements.
Statement 2- reactants are very ...
0
votes
1answer
29 views
Why does 2+ oxidation state become more stable relative to 3+ oxidation state for first row of transition metals? [duplicate]
I viewed an image showing all the possible oxidation states of each element in the first row of transition metals, and the main oxidation states highlighted in a different colour.
I noticed all ...
2
votes
0answers
25 views
Colour of VO3^-?
To aquire the yellow colour of vanadium ion, it must be present in a 5+ oxdiation state.
This can be acheived (according to my textbook) by adding dilute sulfuric acid to $\ce{NH4VO3}$, then followed ...
0
votes
1answer
48 views
Can the 5+ and 4+ oxidation state of Vanadium ion exist independently?
From my class text book:
The oxidation states of Vanadium ions 5+ and 4+ are shown in the compounds $\ce{VO2^{+}}$ and $\ce{VO^{2+}}$ respectively, whereas $\ce{V^{3+}}$ and $\ce{V^{2+}}$ are ...
-1
votes
1answer
75 views
The second Ionisation energy of the Zn, Cd, and Hg follows the order?
It is observed that the order of second ionisation energy of these three elements is Zn > Cd < Hg.
Why is there an anomaly in the observation?
0
votes
1answer
95 views
Why is chromate coloured but tungstate colourless?
I have to try and work this out using the tetrahedral molecular orbital diagram for $\ce{[WO4]^2-}$ but I am confused as both are $\mathrm d^0$ right?
1
vote
1answer
52 views
The number of transition elements
I searched in the internet but most of them said that there are 38 transition metals. But our text book says that group 12 or the group of zinc CAN'T BE COUNTED as transition metals. Which already ...
-4
votes
2answers
78 views
Oxidation state of Manganese [closed]
We know that Mn shows variable oxidation states ranging from +2 to +7 but why is +1 oxidation state of Manganese(Mn) not stable?
The +1 oxidation state of Mn would have a configuration of 4s1 3d5.
...
-1
votes
1answer
38 views
Transition metals and their ability to form coloured ions [closed]
I understand that in solution. transition metals form coloured ions, but what about the transition metals in solid compounds that are coloured- is this also due to d-d transition?
can you give any ...
2
votes
1answer
75 views
Effective Bohr Radius in Transition Metal Complexes?
I am playing around with a toy model of a transition metal complex where the HOMO are $d$-electron states of predominantly transition metal character. Let's say this is a $d^1$ (or $d^9$) system and ...
2
votes
1answer
41 views
Flame test for copper salts
I have read from sources here, here and even in my textbook that Copper (specifically $\ce{CuCl2}$ ) burns with a bluish green flame. All the sources mention that this is due to electron excitation ...
1
vote
1answer
56 views
Does pure iron not rust?
In my school science textbook, written more than twenty years ago, it said that pure iron does not rust. Accompanying was a photograph of an ancient iron statue situated outside, which had not rusted.
...
0
votes
0answers
17 views
Why does manganese have lower enthalpy of atomisation and melting point than chromium? [duplicate]
We know that due to stable half filled 3d5 config of Mn(3d5 4s2) it deviates from the general trend of melting points. However, Cr(3d5 4s1) also has stable half filled d-orbitals yet it has higher ...
1
vote
2answers
330 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
101 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 ...
5
votes
2answers
301 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
63 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
72 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:
$$
\begin{array}{cll}
\hline
\ce{M} & \ce{[M(en)2(H2O)2]^2+} & \ce{[M(...
1
vote
0answers
53 views
Stability order of chelate complexes of nickel and iron
Which stability order is correct?
$\ce{[Ni(en)2]^2+} > \ce{[Ni(dmg)2]}$
$\ce{[Fe(edta)]^2-} > \ce{[Fe(en)3]^3+}$
In the first case I think the stability depends upon the strength ...
1
vote
1answer
52 views
Can oxygen gas in air react with Mn3O4 to form MnO2?
I think $\ce{MnO2}$ at high temperature can be used as a catalyst for $\ce{SO2 + O2 -> SO3}$:
$$
\begin{align}
\ce{MnO2 + SO2 &-> MnSO4}\tag{1}\\
\ce{3 MnSO4 &-> Mn3O4 + SO2 + 2 SO3}\...
1
vote
3answers
99 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
23 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
71 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
62 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
92 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
45 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
69 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
822 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
50 views
CO-vibration in metal carbonyl
I'm struggling to understand the trend of $\ce{CO}$-vibration in isoelectronic metal carbonyls.
$$
\begin{array}{lr|lr}
\hline
\text{Compound} & ν/\pu{cm-1} & \text{Compound} & ν/\pu{cm-1}...
5
votes
1answer
304 views
Is scandium considered a transition metal?
I have seen so many conflicting answers to this question in various places so I wanted to ask it again.
IUPAC defines a transition element as
an element whose atom has a partially filled d sub-...
1
vote
2answers
147 views
Synthesis of potassium trioxalatocobaltate(III) trihydrate
I've synthesized the compound potassium trioxalatocobaltate(III) trihydrate and for it I have two reaction equations. One of them is:
$$\ce{CoCO3 + 3K2C2O4.2H2O -> K2[Co(C2O4)3] + 2CO2}$$
and the ...
16
votes
1answer
1k 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
167 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
vote
0answers
25 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
70 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(...
2
votes
0answers
68 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. ...
6
votes
0answers
96 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
121 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+}$$
using $\ce{Zn}$ as a reducing agent.
the colour turning from green to blue and I know that with contact with air the solution becomes ...
2
votes
2answers
85 views
Colour of metal complexes with the same type and number of ligands
Crystal Field Theory says that because of d-orbital splitting caused by different ligands we have 2 different energy levels for d-orbitals.
It also says that transition metals are coloured because ...
1
vote
1answer
308 views
Products of the reaction between chromium(III) chloride, zinc and sulfuric acid
The aim of my experiment was to make a Cr(II) aquacomplex in situ, and for that I have the reaction:
$$\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
103 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
509 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?
11
votes
1answer
246 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}...
