Question

which changes involve forming or breaking chemical bonds?
o boiling and melting
o rusting and cutting
o burning and digesting
o burning and melting

Explanation:

Chemical changes involve forming or breaking chemical bonds. Burning is a combustion reaction that forms new substances by breaking and forming chemical bonds. Digesting food also involves chemical reactions to break down complex molecules into simpler ones. Boiling and melting are physical changes that only change the state of matter without altering chemical bonds. Cutting is a physical change that just divides a substance physically. Rusting is a chemical change but cutting is not. Burning and melting - melting is a physical change.

Answer:

burning and digesting