The energy stored in molecular bonds is called a heat b atomic energy c chemical energy d mechanical energy

The answer for #3 is c but i don't know why

Achange in the number of neutrons in an atom will change an blank . when the number of protons changes in an atom, a new element will form.

Choose all the answers that apply. ionic compounds dissolve easily in water do not dissolve in water have low melting points have high melting points conduct electricity when melted