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What's the third most common element?

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Re: What's the third most common element?

#51

Post by ethbro »

Someone wrote: post #48
autokad wrote: post #46

Earlier quoted context omitted.

when you roll 2 dice, you get a lot more evens than odds. i imagine the same principle holds. if an odd (Hydrogen) forms with another odd, you get even. Hydrogen+helium=odd, but helium + helium = even. as the evens outnumber the odds, even more evens are forming with evens.

No, you don't 1+3+5+5+3+1 = 2+4+6+4+2 (1/36 probability of a sum of 2, 3/36 of a sum of 4, etc)

Was going to say, read that, did it in my head.

D1 = {E,O} D2 = {E,O} *Where E and O are balanced in terms of possible outcomes that satisfy

Outcomes: {EE, EO, OE, OO} Odd outcomes: {EO, OE}

Half.

Re: What's the third most common element?

#52

Post by autokad »

Someone wrote: post #48
autokad wrote: post #46

Earlier quoted context omitted.

when you roll 2 dice, you get a lot more evens than odds. i imagine the same principle holds. if an odd (Hydrogen) forms with another odd, you get even. Hydrogen+helium=odd, but helium + helium = even. as the evens outnumber the odds, even more evens are forming with evens.

No, you don't 1+3+5+5+3+1 = 2+4+6+4+2 (1/36 probability of a sum of 2, 3/36 of a sum of 4, etc)

oh yeah your right

Re: What's the third most common element?

#53

Post by Agathos »

What are the six most common elements in the universe?

H, He, C, N, O, Ne

What are the four most common elements in living cells?

H, C, N, O

(We invited the noble gasses to play, too, but they said something along the lines of, "Go away you peasants you'll mess up our perfect orbitals.")

Re: What's the third most common element?

#55

Post by peter303 »

natejenkins wrote: post #11

What caught my eye was the oscillation in the abundancy graph, there is a tendency for even atomic number elements to be more abundant than odd atomic number elements. Looking at the original Wikipedia article leads to the Oddo-Harkins rule http://en.wikipedia.org/wiki/Oddo%E2%80%93Harkins_rule . There is more discussion on the stability of even vs odd atomic number elements here: http://en.wikipedia.org/wiki/Even_an…

alpha fusion (He nucleus) is lower energy than proton fusion

Re: What's the third most common element?

#57

Post by arto »

As for lithium (the third-most abundant element after the Big Bang, at 0.00000001% of nuclei), it so happens I was just reading the James S. A. Corey novel Cibola Burn where it plays a role:

"People used to think gold was worth fightin' over, and that shit gets made by every supernova, which means pretty much every planet around a G2 star will have some. Stars burn through lithium as fast as they make it. All the available ore got made at the big bang, and we're not doin' another one of those. Now that's scarcity, friend."

Re: What's the third most common element?

#58

Post by stephengillie »

natejenkins wrote: post #11

What caught my eye was the oscillation in the abundancy graph, there is a tendency for even atomic number elements to be more abundant than odd atomic number elements. Looking at the original Wikipedia article leads to the Oddo-Harkins rule http://en.wikipedia.org/wiki/Oddo%E2%80%93Harkins_rule . There is more discussion on the stability of even vs odd atomic number elements here: http://en.wikipedia.org/wiki/Even_an…

The underlying mechanics are highly theoretical, but it has something to do with the quarks that compose protons and neutrons. The Strong force is theorized to be caused by color-charge attraction. It would be the same situation as if photons (light, etc) were highly magnetic, they'd attract molecules; in this way the charge carriers of the 3-way color force are highly (and mutually) attracted to quarks for their color-charge.

There's a radius for color-charge interaction. This radius is thought to be one cause for larger elements being less likely to be stable; when protons are too far apart to exchange color-charge carriers, their magnetic repulsion can disrupt nucleic stability.

And different quarks have different energies. Every neutron has 2 Down quarks and 1 Up quark (UDD); every proton has 1 Down quark and 2 Up quarks (UUD). Down quarks are more energetic (massive) than Up quarks. After about 5 minutes, a neutron (UUD) decays into a proton (UDD), an electron, and an electron neutrino. This would seem to imply that an electron and a neutrino would equal the difference between an Up and Down quark.

All protons and neutrons have 3 quarks. There are other particles with 2, but they're much more rare. Nuclei with an odd number of nucleons (protons and neutrons) would have to have an even number of quarks. There may be something to the number of quarks, research into that is difficult because the act of pulling quarks apart requires so much energy that it just creates new quarks.

[1]http://en.wikipedia.org/wiki/Neutron

Re: What's the third most common element?

#59

Post by cabinpark »

simonh wrote: post #26
mrfusion wrote: post #24

I've always wondered how elements produced in past stars end up in our solar system. I wouldn't think the whole universe is getting remixed all the time. It seems like areas stay pretty isolated.

At the universal scale, we can observer several galaxies in various stages of colliding with each other (1). In fact our galaxy and Andromeda are on course to collide with each other in about 4 billion years (2). Massive stars end their lifecycle in a supernova explosion, which blasts much of their mass off into space. the remaining stellar core either forms a neutron star or a black hole. The mass that is blated off…

This is actually my PhD research! Yes the current thought is that neutron star mergers are the source of heavy elements (iron and greater) over supernova. Looking at the elements produced by nucleosynthesis from the outflow yields very positive results when compared with abundance curves in our solar system.

Also because we know how much material is released in a mrger and how much material there is in our galaxy, we can work out how frequent neutron star mergers are and these results agree with other independent estimates of frequency of merger.

Re: What's the third most common element?

#60

Post by hga »

arto wrote: post #57

As for lithium (the third-most abundant element after the Big Bang, at 0.00000001% of nuclei), it so happens I was just reading the James S. A. Corey novel Cibola Burn where it plays a role: "People used to think gold was worth fightin' over, and that shit gets made by every supernova, which means pretty much every planet around a G2 star will have some. Stars burn through lithium as fast as they make it. All the ava…

Naw, or at least according to what I've been reading lately we get lithium and a number of other light elements from cosmic ray spallation: (https://en.wikipedia.org/wiki/Cosmic_ray_spallation so it's happening all the time.
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