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Nucleosynthesis is the process that creates new atomic nuclei from pre-existing nucleons, primarily protons and neutrons. The first nuclei were formed about three minutes after the Big Bang, through...

Atoms heavier than hydrogen were made by what - Answers


Atoms that are heavier than hydrogen were made by nuclear fusion after the big bang. Initially, only the lightest element, hydrogen, was present.

How elements are formed | Sciencelearn Hub


Oct 22, 2009 ... An element is a pure substance made of atoms that are all of the same type. ... ' Big Bang', only the lightest elements were formed – hydrogen and helium ... which allows elements heavier than iron, such as uranium and gold, ...

If elements heavier than hydrogen were/are only created through ...


I think I understand your dilemma: you are wondering why, if high temperatures and high .... You assume that heavier atoms at higher temperatures => lighter particles at colder ted ... How were the heavy elements from iron to uranium made?

Anything with an atomic number greater than 92 - Science ...


An answer to the question: How are elements heavier than uranium created? ... We generally call the transuranics "man-made" elements because they are normally not ... of how many neutrons it has) is hydrogen, an atom with two protons is helium, etc. ... Earlier, we said uranium and other heavy atoms were fissionable.

Why did the Universe start off with Hydrogen, Helium, and not much ...


Jul 5, 2013 ... Practically all of these heavy elements were formed in generations of stars: ... the Universe was made out of about 92% hydrogen atoms and 8% helium atoms ... and why didn't more of the Universe become helium than it did?

NOVA - Official Website | The Star In You - PBS


Dec 2, 2010 ... Just what do astronomers mean when they say we're all made of star stuff ... All except atoms of hydrogen and one or two of the next lightest elements. They were formed even earlier, shortly after the Big Bang began 13.7 billion years ago. .... But stars do form elements heavier than iron, including cherished .....

BBC - GCSE Bitesize: Fusion in stars


Nuclear fusion involves two atomic nuclei joining to make a large nucleus. Energy is released ... A hyrdogen-1 nucleus is made of 1 proton. This can combine ... Heavier elements than hydrogen and helium (up to iron) are formed. Elements ...



Their relative abundance (by weight) was 75% hydrogen and 25% helium. ... Second, the atoms were becoming packed more tightly, increasing the density, ... (lower temperature and pressure) than the carbon-nitrogen-oxygen cycle. ... the temperature and density to reach levels where C nuclei can fuse into heavier nuclei.

The big bang left the universe with its first atoms

www.haystack.mit.edu/edu/pcr/Astrochemistry/3 - MATTER/nuclear synthesis.pdf

In the very beginning, both space and time were created in the Big Bang. It happened 13.7 ... how helium is made in our sun, the CNO cycle which explains how hydrogen is fused in hotter stars, and the triple alpha process which accounts ... Creating elements heavier than iron requires energy, it doesn't release energy.

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Stellar Nucleosynthesis - Astronomy Notes


Jun 8, 2010 ... All of the atoms on the Earth except hydrogen and most of the helium are ... made of carbon atoms, hydrogen atoms, and oxygen atoms (C6H12O6). ... The atoms heavier than helium up to the iron and nickel atoms were made ...

Origin of elements and stellar evolution


Sep 10, 2004 ... Hydrogen is the simplest possible atom by definition, one proton and one ... the universe was also expanding, and the chances of collision were getting smaller. ... Elements heavier than iron are made in such explosions.

If iron is the heaviest element made by nuclear fusion, then how do ...


"If iron is the heaviest element made by nuclear fusion, then how do we have so many elements ... Looking at this, we see that hydrogen and helium were primordial (though there ... high-energy particles (i.e. "cosmic rays") hit heavy atoms and produce lighter atoms. ... All elements other than hydrogen are made by fusion...