Questions tagged [rare-earth-elements]
According to the IUPAC, the rare earth elements are a group that comprises the fifteen lanthanoides (La to Lu), Y and Sc. These elements are commonly grouped together due to the similarity in their chemical properties.
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Why is there anomalous trend in third ionization energy for Pr-Pm and Dy-Er?
It is not hard to observe the anomalously flat regions at Pr-Pm and Dy-Er in the trend of IE3 of lanthanides:, each described as the "first quarter" and "third quarter". Why is ...
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What is the purpose of the reflux ratio for solvent extraction?
Not distillation
If I understand it correctly, in my example, one has two components, A and B, starting at the "feed" in the aqueous phase. They get both extracted in the mixer settler, but ...
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The separation of lanthanum oxide and chromium oxide
I have encountered a problem. How can I separate the alloy of lanthanum oxide and chromium oxide? I attempted to dissolve them in concentrated sulfuric acid with heating, but it didn't work. If I had ...
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f-f transitions and their cause
I was looking at this question:
How can f-f transitions happen?
And got some answers that answered some of the questions I had, but not all. I am still trying to conceptually grasp why f-f transitions ...
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What do we use Rare Earth Elements/ lanthanides for in geochemistry? [closed]
What kind of things are lanthanides used for in geochemical studies in terms of high temperature igneous systems and dating rocks from the earth, moon, and solar system?
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Measuring Rare Earth Element Concentration in a Solution
I am interested in repeating the experiment as detailed in this paper: Study on Rare Earth Elements Leaching from Magnetic Coal Fly Ash by Citric Acid
In the paper, coal fly ash is leached by citric ...
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What are observationally stable elements?
According to Wikipedia, a lot of the elements that have higher atomic numbers than dysprosium have isotopes that say "Observationally stable" instead of stable, for example in Isotopes of ...
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Why do the lanthanides usually use the +3 oxidation state?
This might seem like a silly question, but why do all of the lanthanides use the +3 oxidation state? I know that some of them can use the +2 (europium, ytterbium) and the +4 (terbium, cerium, ...
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How many elements have been identified for which there are no known spectral lines?
Background:
@ProfRob's answer to If there were undiscovered elements (119 on) in a star's spectral lines, could we tell? in Physics SE begins:
I think that would be very difficult indeed. ...
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In Lanthanides, Why is electron removed from 4f before 5p? [duplicate]
I've been taught that electrons are removed first from valence shell electrons with highest energy. But In Lanthanides, for example taking configuration- [Xe]4f⁴6s², If we go to +3 Oxidation State, ...
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Why are the rare Earth elements divided into light and heavy categories?
Rare Earth's up to z=62 (Samarium) are often called 'light' rare Earths, while z=63 (Europium) and beyond are sometimes referred to as 'heavy' ones. Why such distinction? I didn't have come across (or ...
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Why can’t lanthanum through lutetium and actinium through lawrencium all be in group 3?
In 2015, IUPAC established a task force to “deliver a recommendation in favor of the composition of group 3 of the periodic table.” Not much about their decision-making process has been made known to ...
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Why do the lanthanides and actinides have a 5d and 6d orbital, respectively? [duplicate]
I was taught in school that the rare earth metals were the $\mathrm{f}$-orbital group. Additionally, the Aufbau principle states that the order of orbitals based on energy levels is $\mathrm{6s4f5d}$ ...
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To what degree can the Rare Earth Elements be interchanged in its workaday applications?
In their humdrum pedestrian "high-tech applications due to their unique magnetic properties", how interchangeable are the Rare-Earth Elements (REEs) if, e.g., the US lacks one of them?
RRautamaa ...
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Magnetic moment of trivalent lanthanide cations
The effective magnetic moment $\mu_{\mathrm{eff}}$ of tripositive rare earth elements, is calculated by $$\mu_{\mathrm{eff}}=g_J\sqrt{J(J+1)}\mu_\mathrm{B}$$
Why can't we use normal formula as $\sqrt{...
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