Chemical reactions -
a. produce new substances.
b. create and destroy atoms.
c. occur only in living organisms .
d. only occur outside living organisms.

High-energy and unstable.

The atomic nucleus made up from protons (yellow) and neutrons (blue) and held together by nuclear forces. nuclear forces (also known as nuclear interactions or strong forces) are the forces that act between two or more nucleons. they bind protons and neutrons (“nucleons”) into atomic