The obvious answer is hydrogen and helium plasma but the nuclear fusion can also create heavier elements. Are these heavier elements a significant portion of the core? Do the heavier elements "sink" ...
I've heard a few times that the Sun's energy output per unit volume is less than that of a human, with the Sun's much higher power output being a result of its much greater size. In a blog post, ...
I've heard in a lecture that a star like the sun would burn 3% of its Hydrogen before expiring. I would have thought it would be much more.