Answer: -
Bond dissociation energy is the energy required to dissociate two atoms with covalent bonds.
This energy must be supplied during the course of a reaction.
Interesting to note that not all the bonds need to be broken during a chemical reaction, only the ones involved in the reaction.
Answer is
3) how much mass per unit of volume is in a substance
Physical changes<span> only </span>change<span> the appearance of a substance, not its chemical composition. Chemical </span>changes cause<span> a substance to</span>change<span> into an entirely substance with a new chemical formula. Chemical </span>changes<span> are also known as chemical reactions.</span>
Answer:
the answer is 4 because 3 just have d orbitals