Questions tagged [elements]

Questions with this tag should involve the elements on the periodic table and their different properties.

264 questions
123
votes
7 answers

Why are most metals gray/silver?

Why do most metals (iron, tin, aluminum, lead, zinc, tungsten, nickel, etc.) appear silver or gray? What makes copper and gold have different colors? What atomic characteristics determine the color?
116
votes
11 answers

Why do fusion and fission both release energy?

I only have high school physics knowledge, but here is my understanding: Fusion: 2 atoms come together to form a new atom. This process releases the energy keeping them apart, and is very energetic. Like the sun! Fission: Something fast (like an…
61
votes
6 answers

What enables protons to give new properties to an atom every time one is added?

How does adding one more particle to the nucleus of an atom give that atom new properties? I can see how it changes it's mass, that's obvious... But how does it give that new atom different properties like color? A good example would be: start with…
58
votes
3 answers

Why is hydrogen the most abundant element in the Universe?

Hydrogen is the most abundant element in nature. Does cosmological nucleosynthesis provide an explanation for why is this the case? Is the explanation quantitatively precise?
46
votes
3 answers

What is the origin of elements heavier than iron?

In all the discussions about how the heavy elements in the universe are forged in the guts of stars and especially during a star's death, I usually hear that once the star begins fusing lighter atoms to produce iron (Fe) that's the end of the star's…
Zubin
  • 573
44
votes
4 answers

Why do "relativistic effects" come into play, when dealing with superheavy atoms?

I have now read on the Wikipedia pages for unbihexium, unbinilium, and copernicium that these elements will not behave similarly to their forebears because of “relativistic effects”. When I read about rutherfordium, it too brings up the relativistic…
44
votes
3 answers

At what temperature are the most elements of the periodic table liquid?

For elements where 'liquid', is relatively easy to define, at which temperature are the most elements liquid, and which ones? Assume 1 atm
yolo
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42
votes
5 answers

Are there individual protons and neutrons in a nucleus?

The popular science material always talks about the number of protons and neutrons in a nucleus, but I've always wondered if that's a real thing nuclear physicists believe or if it is just a convenient model. In other words, is there some reason to…
35
votes
5 answers

Why is argon a noble gas but not, say, beryllium or palladium?

Why is argon a noble gas given that the 3d subshell is still empty? More generally, why is it that the filling of a p sub-shell makes an element noble rather than s, d, or f sub-shells, or completed n-levels? Let's start with the prior that in a…
29
votes
3 answers

Why the distribution of elements on Earth?

I've been wondering exactly why the elements are distributed the way they are on Earth. The heavier elements have their origins in the centers of stars, or in supernovae. After the death of the stars, you end up with a dust cloud containing the…
27
votes
3 answers

If iron can’t undergo fusion, does that mean a black hole is mostly iron?

Since stellar fusion can’t progress beyond iron, and a large enough star collapsed into a black hole because an iron core stalled fusion, wouldn’t that mean all black holes are predominantly iron?
24
votes
1 answer

Why is helium-4 the only nuclide with a negative nucleon binding energy?

He-4 is very unusual as it’s the only nuclide that does not accept another nucleon. In other words, even if you force a proton or a neutron into He-4, it will be kicked out immediately. If you irradiate liquid helium with neutrons, it will cool the…
24
votes
3 answers

Why is oxygen the third most abundant element?

I was reading the article Oxygen finally spotted in space today in which it stated Oxygen is the third most abundant element in the cosmos, after hydrogen and helium. Why would oxygen take the third spot when it is so heavy (relative to the…
corsiKa
  • 1,057
23
votes
4 answers

Why does amount of protons define how matter is?

My question might sound convoluted but my mind is twisting right now so my apologies in advanced. Why is it that when I have one proton and one electron it is Hydrogen a clear flammable gas, and when I have say, twelve, it is carbon the driving…
22
votes
4 answers

Can there be an atomic nucleus where there are more protons than neutrons?

As far as I know, number of protons is less that or equal to the number of neutrons in any atomic nucleus. But is there any possibility that there exists a nucleus where the number of protons exceeds number of neutrons (apart of course, from the…
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