The outermost energy shell of an atom
because they are involved in forming bonds
Answer: Ions are formed by the addition of electrons to, or the removal of electrons from, neutral atoms or molecules or other ions; by combination of ions with other particles; or by rupture of a covalent bond between two atoms in such a way that both of the electrons of the bond are left in association with one of the ...
Planck suggested that light/energy was absorbed/released in certain amounts, called quanta.
Answer: Potassium perchlorate
Explanation: