> Yes, water is common—in fact, it is the third most common molecule in the universe.
What are the first 2 most common molecules? H2 and O2?
In another thread on HN this morning, we learned that Hydrogen, Helium, & Oxygen are the 3 most common elements in the universe. To tangent off a different commenter's remark, the 1st and 3rd most common elements in the universe create the 3rd most common molecule.
I have never seen that definition and I can't find it online anywhere. Wikipedia gives 6 pretty solid looking references for the "two or more atoms" definition.
The same Wikipedia page on molecules that says they have "two or more atoms held together" also says this in the next paragraph:
In the kinetic theory of gases, the term molecule is often used for any gaseous particle regardless of its composition. According to this definition, noble gas atoms are considered molecules despite being composed of a single non-bonded atom.
I'm almost positive that the linked PNG has no attached color profile. There are many browser color correction problems; this is an image authoring problem.
I was really surprised that both of my browsers have bad color correction. What's nice is the pdf confirms this: this are wrong in the browser, but right in the external pdf.
I see no red in your screenshot, but the image on nautilus appears red, they may have fixed the error (either that or your browser is very weird and renders red to blue)
Maybe they updated the image afterward? If so, I like how they sent the correction to the art department and not to a copy editor to fix a few characters.
That is lovely but doesn't explain why the mismatch exists between the picture being blue and caption for the picture saying red.
"BIG ICE: Liquid water (left) is composed of hydrogen (white) and oxygen (red) atoms arranged in a nearly tetrahedral structure. Common ice, or Ice Ih (right), shows a three-dimensional network that is less dense, explaining why ice floats on water."
Another interesting one about water that is unknown, or at least not proven (many credible theories). Why does hot water freeze faster than cold water.
There seem to be a lot of 'minor' effects. However, the most convincing argument I have seen was simply increased thermal conductivity by partially melting the surface below the container. A good test of this would be to start with a warm container and then add hot or cold water to it.
Bill Nye explained it in his show that hot water evaporates so you are freezing a lesser volume of water.I have no idea if that's correct but that's the assumption I've gone on for the last decade or so.
If we are just talking about ice formation and not the point at which the whole thing freezes, then I would expect there to be many systems where the hotter vessel would form ice quicker when put in a very cold environment. Heat being essentially kinetic energy averaged, the greater the initial energy compared to the available drop, the faster it is for large variations to develop.
What are the first 2 most common molecules? H2 and O2?
In another thread on HN this morning, we learned that Hydrogen, Helium, & Oxygen are the 3 most common elements in the universe. To tangent off a different commenter's remark, the 1st and 3rd most common elements in the universe create the 3rd most common molecule.