Which of these changes involve forming or breaking chemical bonds? which of these changes involve forming or breaking chemical bonds? a burning and melting b burning and digesting c rusting and cutting d boiling and melting .

the answer is B hope this helps

The right answer is B burning and digesting

Combustion (burning of molecules) is an exothermic oxidation-reduction reaction. When the combustion is intense, it results in a flame or an explosion (deflagration or detonation if the flame front exceeds the speed of sound).

This chemical reaction is a recombination of molecules. It goes through an intermediate step during which the molecules are "destructured" but not yet recombined; these are called radicals and are very reactive. In the case of combustion, the radicals are created by chemical bond breakage due to thermal energy, and they will be able to act on the molecules of the product (releasing other radicals) and thus generating a chain reaction that will continue as long as the following two conditions are met: presence of fuel and oxidizer.

Digestion is a food processing that is ingested into smaller particles that can or can not be assimilated by the body.

In chemical digestion, polysaccharides such as starches and glycogen are degraded to monosaccharides. The same for proteins that are degraded into amino acids ...

affects the water bodies: excessive use of fertilizers causes eutrophication. the fertilizers which are used on plants affect the quality of land on which it is used, further causing erosion of soil. the fertilizers used on plants contain harmful chemical fumes which affect the environment.