Most abundant elements in the universe
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Hydrogen and Helium: The Most Abundant Elements in the Universe
Hydrogen is the most abundant element in the universe, making up about 90% of all atoms and roughly 75% of the universe’s mass. Helium is the second most abundant, and together, hydrogen and helium account for over 98% of all known matter in the universe. All other elements combined make up only about 2% of the universe’s mass 1SearsJr.2015OpenStax2016+5 MORE.
Distribution and Formation of Elements in the Universe
Hydrogen and helium were primarily formed during the Big Bang, with hydrogen being the simplest and lightest element, consisting of just one proton and one electron. Helium was also produced in large quantities during this time. Heavier elements, such as carbon, nitrogen, and oxygen, are much less common and were formed later inside stars through nuclear fusion processes Randich2021Lehrer1999Wilson1999.
Other Abundant Elements: Carbon, Nitrogen, and Oxygen
After hydrogen and helium, the next most abundant elements in the universe are carbon, nitrogen, and oxygen. These elements are still far less common than hydrogen and helium but are among the most prevalent of the heavier elements. They play important roles in the chemistry of stars, planets, and living systems Randich2021Lehrer1999.
Elemental Abundance in Different Environments
While hydrogen and helium dominate the universe as a whole, their abundance is much lower on Earth, where elements like oxygen, silicon, and iron are more common in the planet’s crust. However, this is not representative of the universe at large, where hydrogen and helium remain overwhelmingly dominant 1SearsJr.2015Lehrer1999+1 MORE.
Conclusion
In summary, hydrogen is the most abundant element in the universe, followed by helium. Together, they make up the vast majority of all matter. Carbon, nitrogen, and oxygen are the next most abundant elements but are present in much smaller amounts. The distribution of elements in the universe is a result of processes that began with the Big Bang and continue in stars today 1SearsJr.2015OpenStax2016+7 MORE.
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