Directly inside a nuclear explosion the temperature is several million degrees. At this temperature everything turns to plasma (highly ionized gas). You would not become ash, dust, or get charred; you would vaporize to gas and most of the electrons would be stripped from the atoms of the gas. Sometime later as this material cooled your atoms would condense out on tiny particles that had been lifted by the updraft into the mushroom cloud and you would become part of the radioactive fallout.
Note, you could not be at the exact center of a nuclear explosion, as this point is inside the physics package of the device which is usually much smaller than a human.
If it's a big enough explosion it will become a supernova
A slice of white bread placed under a grill or in a toaster will become slightly charred and become toast. If left long enough, the toast will become a black cindery object fit only for the bin.
Depends on the power of the nuke. At the center of the explosion the destruction is total. Farther, damages become less destructive, but the radioactive cloud can travel tens or hundreds of kilometers.
Nuclear fusion. Hydrogen atoms combine to become helium, and as a product if that reaction a tiny amount of energy is released as an explosion.
it may take up to 100 years for the explosion area to become livable once again
Bread becomes toast - when it's heated so the surface of the slice is charred.
Nuclear waste. Consumable Energy. Heat.
If sufficient mass remains after the supernova explosion, it will become a black hole.
1983
1956
1949
The real question is why has population explosion forced man to become horrible sepllers?