Questions tagged [allotropes]
Different forms of an element which exist in the same state but have different molecular or crystalline structures. Classic examples of allotropes include diamond and graphite (allotropes of carbon), red phosphorous and white phosphorous, and $\ce{O2}$ and $\ce{O3}$ (allotropes of oxygen).
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Are homoatomic molecules like ozone, graphite, diamond considered as elements [closed]
While researching I have found two definitions for element.
First, elements are pure substances that consist only one type of atoms. According to this O2, O3, Diamond and in short all allotropes are ...
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Is the acceleration of the low-temperature allotropic conversion of β-form white tin by the presence of α-form grey tin really considered catalysis?
discussion of the allotropes of sulfur in Melting point of sulfur and comments below reminded me of Napoleon's buttons, cf. Tin pest; Allotropic transformation. That section in its entirety reads:
At ...
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Melting point of sulfur
The melting point (m.p.) of rhombic sulfur is 385.8 K while the m.p. for monoclinic sulfur is 392 K. Also, the transition temperature of rhombic to monoclinic sulfur is 369 K.
Now, consider heating ...
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Is this a correct Lewis Dot structure for ozone? [duplicate]
I drew a Lewis dot structure of ozone but when I look online it is a bit different. Can I make the single covalent bonds like a triangle that connects all three atoms or is that not allowed? If so, ...
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Why is octaoxygen diamagnetic?
I tried considering that according to LCAO-MO theory $\ce{O2}$ is paramagnetic, which is confirmed by experimental evidence. Since octaoxygen has the crystal structure in figure, I thought there is a ...
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Why does the stratosphere have a lot of ozone, but not the Earth's surface?
Ozone ($\ce{O3}$) and dioxygen ($\ce{O2}$) are both allotropes of oxygen. However, nearly 90% of all ozone is found in the stratosphere, whereas near the earth's surface (or overall in the troposphere)...
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Is ozone paramagnetic?
This answer shows why ozone should be diamagnetic. Still, Wikipedia article says it is weakly paramagnetic, having positive magnetic susceptibility $χ = \pu{+6.7E−6 cm^3 mol^-1}.$ There's a paper ...
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Why do some elements form allotropes and others do not? [duplicate]
I just studied in my chemistry class about the allotropes of carbon. But why does carbon form allotropes? Also why only carbon? Why do some elements form allotropes and others do not?
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Stability of α, β, γ allotropes at different temperatures
While reading about elements or compounds I often come across allotropes (or forms) being referred to as α, β, γ forms.
Examples:
Sulfur has two allotropes: α rhombic and β monoclinic. Out of these ...
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Which allotropes of sulfur exist naturally?
I'm writing a paper on chemistry and I would like to know which allotropes of sulfur exist naturally. I've searched on the Internet but I haven't found anything about natural sulfur allotropes except ...
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What is "activated red phosphorus"?
[WP = white phosphorus ; RP = red phosphorus ; ARP = activated red phosphorus]
A YT channel, Extraction & Ire has a video from two years ago (2018) on converting WP to RP by keeping the former in ...
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Predicting sign of enthalpy of allotropic transition of phosphorus
How to predict the sign of enthalpy during the transition
$$\ce{P(s, white) -> P(s, red)}?$$
$\ce{P(s, red)}$ is more stable than $\ce{P(s, white)}$ due to release in angle strain.
Since during ...
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Can other group IV elements form graphene analogs with interesting properties? [duplicate]
Graphene has gathered quite a bit of press due to its unique physical properties which hold enormous promise in a wide range of applications from semiconductors to high strength materials. Given that ...
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Se+P White or red P?
I read this in an old chemistry book. It says:
When selenium is dropped into melted phosphorus, it dissolves rapidly, and the compound sinks through the liquid phosphorus in red streaks.
My ...
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What is tetrasulfur like? Why is there so little experimental information about it?
Phys.org's How sulfur helped make Earth habitable before the rise of oxygen says
Mapping the bonds and vibrational modes of molecules containing sulfur isotopes is helping to shed light on the ...
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