what 2 types of atoms are not created inside a star?

Question

any atoms larger than these 2 were created in centre of a star, including iron, carbon etc parts that our bodies are full of

Answer 1

The Hydrogen and heavier cousin Deuterium are two atoms that are not created inside a star. All the remaining atoms can be created inside a star through fusion (up to Iron). Elements heavier than iron are created during supernova explosions.

However this does not mean that all the other elements were created inside stars.

Approximately 25% of the helium in the universe was created during the Big Bang. Small amounts of tritium, helium 3 and Lithium were also created in the Big Bang.

You are quite correct. our bodies are essentially star stuff and at one stage many of the atoms, (pretty much everything except Hydrogen), in your body were formed in the core's of massive stars.

Answer 2

Hydrogen and helium are not created in the star, Hydrogen atoms formed the original gas clouds after the big bang that eventually formed into helium, thus creating stars. (Some debate if lithium was around after the big bang too). The fusion of helium and hydrogen causes the creation of other elements (carbon, oxygen, etc.) but nothing heavier than iron can be created by this process. All matter in the universe was created from the fusion of hydrogen and helium and spilled out when the stars exploded. From there, these basic elements began forming new configurations and now we have the periodic table.

I quote a funny dead milkmen lyric: "the goddamned periodic table of the elements they've got 109 or so naturally occurring elements then they've got 10 or 11 of these non-naturally occurring man-made elements and they give em names like einsteinium, californium and nobellium and what i wanna know is: if they're man-made, then how the hell can they be elements? huh?"

Answer 3

Most of the Hydrogen in the Universe was created in the first microsecond after the big bang, when quarks and glueons got together to form protons.

Most of the Helium and Deuterium (an isotope of Hydrogen) was created in the first 15 minutes after the Big Bang, when the universe was the right density and temperature to create these elements. After 15 minutes or so the temperature of the Universe was too low to sustain nuclear reactions. Small amounts of Tritium, Lithium, and Boron were also created in those first 15 minutes.

These light elements are mostly destroyed in stars, by nuclear fusion, although there are some mechanisms to create these elements in the present day (for example, alpha decay or, "spallation events", where a cosmic ray knocks a light element out of a heavy nucleus).

All other elements are made in stars. Stable nuclear fusion tends to "burn" elements to iron, since those nuclear reactions are exothermic. Elements heavier than iron are made in non-equilibrium situations, basically during supernovae.

Answer 4

Cosmo and John H are right on target. Hydrogen is the only element not made in stars. But even deuterium is a part of the proton proton chain and is formed in the cores of stars.

Even though a great quantity of Helium was formed in the big bang, Helium is still the most common by product of Hydrogen fusion.

All other elements up to Iron are formed in regular burning stars.

All other elements heavier than Iron up to E118 (did they ever name that?) and possibly some we don't know about yet are formed during supernova type explosions. Of those formed during the explosion, some are very short lived and decay into other more stable elements very quickly.

Answer 5

As others have said, the two elements are Hydrogen and Helium. Those who say that nothing HEAVIER than Iron are created in a star are incorrect. It is true that nothing heavier than iron is created from NORMAL nuclear fusion reactions inside a star. HOWEVER, heavier elements such as gold and uranium ARE created during the brief moments when a massive star goes supernova. This is why these elements are much rarer than iron.

Answer 6

The only reasonable way to interpret your question is "what two elements are not net created in stars" (ie, reactions that use up as much or more than they create do not count). Hydrogen and Lithium are the ones. Read on to see why other intepretations of the question are not answerable.

Another way to interpret it is to look at temporary creation, but then there is no answer. Deuterium is created inside of stars, but it is also destroyed VERY quickly. Helium3 is created in stars, but it also is destroyed very quickly. (see proton-proton chain again). It fuses easily. Hydrogen itself is created in the Proton-proton chain. In this reaction, more is destroyed than created, but by the same standard, deuterium, and helium 3 are not net created, so that is three kinds of atoms already.

I was hoping to say Lithium, since it is very quickly destroyed through fusion with a single proton and then decay into two helium 4, but Lithium is a possible product of the p-p chain, it is just quickly destroyed also. One might be tempted to suggest Beryllium and Boron, since we think of Helium as triple-alphaing into Carbon, but since Beryllium or Boron were not created in the big bang at the levels we see today, they are created in some kind of explosion.

Answer 7

When the universe was first formed, the only elements were hydrogen and helium. All other elements were created in stars. Contrary to an earlier answer that includes radioactive elements like uranium.

But note that some helium is also created in stars, in addition to the helium being present at the beginning. So, there's only one element that's not created in stars, hydrogen.

Answer 8

hydrogen and man made transuranics are the only elements not made in stars. All those up to iron are created in the fusion processes, others are created from these in the cooler outer parts. IMPORTANTLY there are two fusion cycles, the more common iron cycle which requires H and He to kick it off, and the less common these days helium cycle, which just produces elements helium.

Answer 9

the atoms around iron copper erc. become too heavy eventually for star formation
in theory any radioactive element probably DOESNT come from stars and weve made many of them artificially in labs etc.
the elements go from 1 up to 110 and beyond so the last 20 or so arent found outside nuclear labs.
and they have weird technial names like unnilnonium and unnildecium which only mean 109, 110 etc.

Answer 10

A star starts with hydrogen and using fusion converts it into helium and all the way up to Iron.