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Has mercury(II) cyanate ever isolated as a free compound?

Recently, I answered a question "Comparing explosive properties of mercury(II) cyanate and mercury(II) fulminate" where stability of cyanate vs fulminate was discussed. While I was answering that question, I found out that fulminate vs cyanate stability was previously discussed when chemical isomerism was discovered by Liebig and Wohler. They both reported independently that cyanic acid […]

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How can we say that Helium (He) is liquid at “absolute zero”?

According to Wikipedia, Helium can never be solidified at 1 atm (101325 Pa) pressure, not even at absolute zero. A minimum of 25 atm pressure is required to make Helium solid. But absolute zero (0 K) is not attainable, how can we say that Helium is liquid at absolute zero with 1 atm pressure? It […]

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Why is stacks appearing on my desktop with no files?

Why is Stacks appearing on my desktop with no files? Disclaimer So I’d just like to make clear that this issue isn’t bothering me in any way, but I am simply curious as to whether this is a glitch unique to me or to everyone. Context Since the release of macOS Mojave, a feature called […]

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What causes excessive CPU use by taskgated, notifyd, and launchd processes?

I’ve looked around a lot to try to find the answer to this but have thus far been unsuccessful. I am programming in Python, and I have code that takes a long time to run (hours to months depending on the application) and I am trying to optimize it. On larger thread systems (once I […]

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I need to upgrade my MacBook Air 2017 13′ 256GB SSD to 1TB SDD, I need sutible one for good price and i also i can use bootcamb if can

I need to upgrade my MacBook Air 2017 13′ 256GB SSD to 1TB SDD, I need a suitable one for a good price also I can use Bootcamp or anything that I code run window as well.

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Removing iTunes

I am using MacOS Mojave 10.14.6. I want to remove iTunes completely from my system. I tried to modify the permissions by right clicking changing the " sharing and permissions settings" but the following message appears : "The operation can’t be completed because you don’t have the necessary permission." Can anyone suggest me any solution […]

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Macbook Pro 16″ usb-c to DisplayPort not working

I’m trying to connect a MacBook Pro 16" to my external display through DisplayPort with these devices : Cable Matters Adaptater USB C to DisplayPort DisplayPort Cable External display : iiyama prolite b2783QSU But it’s not working. When I plug it in, the external display goes out of sleeping mode, but the MBP does not […]

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Electronic Structure of Atom,Periodic Table & Periodicity [closed]

Atom Y has nuclear charge of+13 a)Determine the number of electrons that are unpaired b)Give the set of quantum number (n,l,ml,ms) for the unpaired electron(s)

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Molecular Structure

What’s the meaning of the triangle and striped line in this structure of H3O+: Fig Can someone suggest me a site to learn about this? (I’m quite a novice in chemistry.) Thanks

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Why is black-body radiation curve smooth without a sharp cutoff?

Planck’s law is able to predict a graph that is consistent with experimental observation: In essence, unlike Rayleigh-Jeans law that assumes equipartition theorem to hold (that each mode of motion shares equal energy at thermal equilibrium, so all modes excited at thermal equilibrium ⇒ ultraviolet catastrophe), Planck’s hypothesis proposed that oscillators of frequency v will […]