I don’t read Science (the journal) regularly, but news articles like this function as flags for “there may be an new paper worth reading” so I go get it from everyone’s favorite repository of scientific papers. That’s the value.

If you want to critique the state of scientific news writing that’s fine but realize you’re just whining. The fact that it’s about science news isn’t that much different than political news.

After passing a constitutional amendment, would it not be misleading to declare "The US rewrites the constitution" ?

If a 2nd edition of a novel includes a new preface, it would be misleading to advertise the book as "re-written".

You see it as "sexy sounding", I see it as intentionally misleading about the significance of the result.

You can put -ism at the end of any word. In most cases it will just demonstrate an agenda-driven dichotomy. Criticizing a culture of critique requires a culture of critique. So no, HN does not have a problem here and the OP is not whining. This is the system working as intended.

This is exactly what basic theory predicts, but I can’t think of another system that can be tweaked like this to demonstrate that transition so cleanly. Given the weak interaction between the electrons and the ammonia, it can probably be modeled fairly simply, which is nice.

Some selected highlights from the paper, saying, i think, the same thing, in a little more depth (PE = photoelectron, PES = photoelectron spectroscopy):

> The nature of the metallic transition in both liquid and crystalline alkali metal–ammonia systems, directly evidenced by an orders-of-magnitude increase in electrical conductivity, has puzzled researchers for decades and is not yet understood in molecular detail.

> There is thus a clear need for a direct PES investigation of excess ammoniated electrons that would cover both the electrolyte and metallic regimes. We have recently overcome a critical obstacle in collecting PEs from a volatile polar refrigerated liquid.

> This work has paved the way for PES investigations mapping the electrolyte-to-metal transition through the study of liquid alkali metal–ammonia solutions of increasing concentrations, as reported here.

> The present study shows that the electrolyte-to-metal transition in increasingly concentrated alkali metal–liquid ammonia solutions is a gradual process rather than an abrupt first-order transition, which is in line with previous suggestions. From the molecular point of view, this transition may be understood in a simplified way as gradual coalescence of individual solvated electrons and dielectrons upon increasing alkali metal doping, with the metallic behavior appearing around the percolation threshold.

And yeah, TFA is a little lame. I laughed at "lithium...floats on water". It's true that it's less dense, but "float" is a huge understatement. That is, it skitters, like water on a hot frying pan. But, I guess because it's less dense, it doesn't detonate as often as sodium or potassium do.

No, if you wrapped it in some impermeable coating so it couldn't react with water it would still float.

> But, I guess because it's less dense, it doesn't detonate as often as sodium or potassium do.

It doesn't "detonate as often" because it is less reactive than sodium and potassium because it is less likely to lose it's outer electron because that outer electron is closer to the nucleus.

That also means it is denser.

I found a resource that corroborates what I said about behavior on water.[0] But it doesn't get into why that is.

And about density and electronegativity:

        g/cm^3   χ (Pauling)  1st ionization energy (kJ/mol)
   Li   0.535    0.98         520
   Na   0.968    0.93         496
   K    0.856    0.84         419

0) https://www.reference.com/science/alkali-metals-react-water-...

Putting a small lump in a bucket outdoors using a rope-activated rig sounds pretty reasonable, though.

"Intuition suggests that metals are dense, and while that bears true for some (think gold or lead), it fails to hold up for others. For example, lithium—commonly used in batteries—floats on water. Some metals are hard, such as titanium, yet others yield easily to pressure, including indium and aluminum. How about melting temperature? Platinum melts at more than 1,700 degrees Celsius (3,200 F), but mercury is a liquid well below zero.

Many other definitions of 'metal-hood' suffer similar contradictions, but only metals are able to conduct electricity. Conduction, unlike density or hardness, is an inherent property of all metals."

From the article:

"In these solutions, electrons from the alkali metal initially become trapped in the gaps between ammonia molecules. This creates what scientists call 'solvated electrons,' which are highly reactive but stabilized in the ammonia. These solutions have a characteristic blue color. But given enough solvated electrons, the whole liquid turns bronze and, in essence, becomes a metal while remaining liquid.

Solvated electrons have proven to be important to organic chemists. Through a reaction called the "Birch reduction," named after chemist Arthur Birch, they were key to synthesizing many important compounds and led to the manufacture of oral contraceptives in the 1950s."

Any substance that contains free electricity carriers will conduct electricity. Examples of electrical conductors that are not metals: 1. Liquid electrolytes 2. Solid electrolytes 3. Semiconductors 4. Ionized gases 5. Vacuum in which electrons or ions have been injected by some means All of the above are used in common devices.

The metals are solid or liquid electrical conductors which contain free electrons that are intrinsic, i.e. not produced by various methods, like in semiconductors.

Besides free electrons, metal have a second characteristic, which was used already in the 18th century to distinguish metals from semi-metals.

While this distinction is seldom mentioned nowadays, it remains useful. Metals have both free electrons and a crystal structure that allows plastic deformation (i.e. with high coordination number), while semi-metals have free electrons, but they have a crystal structure that does not allow plastic deformation, i.e. they are fragile. Examples of semi-metals: graphite, antimony, bismuth.

The article is incorrect on this. Some non-metals can conduct electricity.