since only H and He were formed in the begining of the universe, where did the rest of the elements come from?

Answer 1

As the Universe cooled electrons were captured by the primitive atoms and heavier atoms were able to form, such as Be and Li.
The lightest elements (hydrogen, helium, deuterium, lithium) were produced in the Big Bang nucleosynthesis. According to the Big Bang theory, the temperatures in the early universe were so high that fusion reactions could take place. This resulted in the formation of light elements: hydrogen, deuterium, helium (two isotopes), lithium and trace amounts of beryllium.

Nuclear fusion in stars converts hydrogen into helium in all stars. In stars less massive than the Sun, this is the only reaction that takes place. In stars more massive than the Sun (but less massive than about 8 solar masses), further reactions that convert helium to carbon and oxygen take place in succesive stages of stellar evolution. In the very massive stars, the reaction chain continues to produce elements like silicon upto iron.

Elements higher than iron cannot be formed through fusion as one has to supply energy for the reaction to take place. However, we do see elements higher than iron around us. So how did these elements form? The answer is supernovae. In a supernova explosion, neutron capture reactions take place (this is not fusion), leading to the formation of heavy elements. This is the reason why it is said that most of the stuff that we see around us come from stars and supernovae (the heavy elements part). If you go into technical details, then there are two processes of neutron capture called rapid process (r-process) and the slow process (s-process), and these lead to formation of different elements.

Answer 2

there wasnt on those 2 elements, there were some heavier elements, there was actually probably a little bit of heavier elements that we have been able to create here on earth.

but the majority of elements come from stars. gravity collapses a massive cloud of hydrogen and as that happens the pressure and temperature increase. when both of those are high enough hydrogen atoms will smash into eachother and fuse to form hydrogen. the resulting helium ion is slightly less massive than the hydrogen ions that went into making it, its less by about 4%. that 4% is given off as heat and light energy. that process is called thermonuclear fusion.

in a star like our sun the hydrogen will be fused into helium, then the sun will start to collpase. it will collapse until it can fuse helium into carbon and oxygen and then it will expand. thats the end of the line for stars like our sun because they are not massive enough to fuse carbon into anything.

more massive stars a different. they dont need to shrink and obtain a greater pressure and temp to fuse elements higher than hydrogen, they just start to fuse them right from the start. so what you get is a star with layers, the outer one hydrogen and then there is a layer of the first 25 elements and then an iron core.

the reason its an iron core is that fusion of iron actually requires energy, it doesnt give it off. so its hard and useless to fuse (in nuclear weapons they use nuclear fission, which is basically splitting the atom, which would release energy if it was larger than iron).

when a mass star "dies" the iron core very very rapidly expands. its more of a very sudden push outward. that pushes all of the other elements out into space at a large fraction of the speed of light, thats what a supernova is. that iron core then remains, the electrons and protons are combined into neutrons because of gravity trying to collapse it. and you get a star made of entirely neutrons, a neutron star. if the star is too massive it forms a black hole.

but ive strayed from the question. any elements above iron come from the very small amount fused in massive stars, from the big bang, or from supernovas (they have massive energy).

Answer 3

Almost all of the heavier elements are generated from fusion reactions in the cores of very massive stars. These same stars more often than not explode as supernovae. Under the tremendous pressure and temperatures of these events, the heaviest elements are 'cooked' up and blown outward into open space.

Answer 4

A good question. Ordinary stars like the Sun produce the elements from lithium to iron inclusive. But the only process I know about that produces elements heavier than iron is a supernova.

Answer 5

All elements up to iron were formed in regular stars, heavier elements were formed in the massive temperatures and pressures of super novae. These elements were hurled into space when the giant star collapsed, they seeded other stars.

Answer 6

There was also some Lithium at the beginning, but it was an isotope that no longer exists.

The rest of the elements were synthesized in the first stars that went supernova. New elements are still being made in massive stars. Each supernova produces huge amounts of just about every element that currently exists in nature.

Answer 7

no longer in easy terms helium and hydrogen yet in addition each and every of the mass interior the universe grow to be additionally created with the BB. yet we come from a action picture star that died, the capability and the components that a action picture star demise produces is what's mandatory to supply extra stars and planets- each and every of the climate we hit upon are already interior the solar.

Answer 8

i believe everything heavier than Iron was formed in super nova, the lighter elements are formed in stars

Answer 9

The interior of stars.

Answer 10

fusion