How do the fusion reactions in the sun compare to the fusion occuring in larger stars and supernovas?

Answer 1

An interesting question and a complicated one to answer. You will have to do some reading and understand the basics of nuclear reactions, to be able to grasp the details. The main difference between stars of the sun's size and larger stars is the temperature of the interior and this makes different reactions predominate. In the sun it is the proton-proton reaction which is most important. In larger stars with higher temperatures a more complicated chain results which includes a carbon-nitrogen-oxygen cycle. In both cases the starting point is nuclei of hydrogen and the end point is nuclei of helium, with energy being released.

You can find out more in Wikipedia entries 'Proton-proton chain reaction' and 'CNO cycle', but be warned, you will have to concentrate hard!

Answer 2

More massive stars have higher pressure in their cores which allows heavier elements to be produced.

Supernova are so hot that all the natural elements may be produced.

Our sun can only burn Hydrogen today, although someday it will burn Helium.

Answer 3

Different stars have different fusion reactions, depending on their mass and on random probability.

In our Sun, a G Type Main Sequence star that is relatively small, in the grand scheme of things, the primary reaction is the proton-proton (P-P) chain reaction, although some (about 2%) of the reactions are the carbon-nitrogen-oxygen (CNO) cycle reaction.

In the P-P chain reaction, four protons from hydrogen are fused to create a helium nucleus, with the weak interaction changing two of the protons into neutrons. Energy is released due to the mass deficit of the nucleons at a rate of about 26.7 MeV per event or, for our Sun, at a rate of about 3.846 x 1026 joules per second, which is equivalent to about 9.192 x 1010 megatons of TNT per second. (And you thought a hydrogen bomb was large!)

On the other hand, the CNO cycle also fuses four protons, but it uses carbon, nitrogen, and oxygen as catalysts. The choice depends on mass and temperature. For stars about the mass of our Sun, the P-P chain dominates, whereas for stars greater than about 1.3 times the mass of our Sun, the CNO cycle dominates, because of the higher temperatures involved.

There are other reactions possible, but the P-P chain and the CNO cycle are primary. For more information, please see the Related Link below.

Answer 4

Nuclear fusion takes place in both big and small stars but followed by different mechanism. In small star like our sun nuclear fusion is followed by proton-proton chain reaction in which hydrogen converted into helium but in bigger star nuclear fusion is because of carbon nitrogen oxygen cycle. Also in bigger star heavy elements can burn up. The lifespan of big star is less than small star because it requires high enrgyy and therefore it consumes it's resources more quickly

Answer 5

The fusion reaction in the Sun is the same as that in all main sequence stars. However in a supernova the fusion reaction in the core of the star stops (with the production of iron) and it is this that causes the star to explode.