“As for crack and powder being the same chemically, that is not true.”
The difference .HCl
One is a free base in a salt matrix, the other is the hydrocloride salt. The base molecule may be “cocaine” but the free base and the salt are not the same chemically or physically, nor do they “dose” the same.
The reason you bake cocaine HCl with sodium bicarbonate is to remove the HCl, freeing the base, which vaporizes much easier. You can smoke cocaine HCl but a lot of it degrades because of the higher temperature.
Cocaine HCl will pass through a mucous membrane so people can insufflate it, but the freebase won’t.