A dead star is one that no longer experiences nuclear fusion. This happens when a star runs out of hydrogen it can use to convert to helium.
A massive collapsed star is a dead star.
A dull star
neutron star
A protostar is a star that is still forming and has not yet started a sustained fusion reaction. All the heat is the result of gasses being compressed. A white dwarf is the remnant of a dead star that has exhausted its fuel and is much smaller and denser than a protostar.
black dwarf
Well, white dwarf, brown dwarf, and neutron stars don't; but they are "dead" stars.
A massive collapsed star is a dead star.
A dull star
it is not a chemical reaction. It is a nuclear reaction and it is called fusion.
it is result of a dead star
neutron star
Yes Umaga is dead.
Technically a dead star is when a star no longer undergoes nuclear fusion. Depending on the mass of the original star this will either be a white dwarf, neutron star or black hole. These are called stellar remnants.
It is not existing
black dwarf
Yes
When it turns into a black dwarf neutron star or black hole.