Which stage of star development comes right after the long stable phase in the life cycle

an ion is a charged atom or molecule. it is charged because the number of electrons do not equal the number of protons in the atom or molecule. an atom can acquire a positive charge or a negative charge depending on whether the number of electrons in an atom is greater or less then the number of protons in the atom.

if the thermos has a vacuum innner, then heat through conv currents and conduction are reduced = vacuum flask