Which of the following describes a chemical reaction?
a. molecules mix without interacting.
b. atoms in substances react with each other.
c. substances change shape but not properties.
d. molecules interact without bonds breaking.

Which of the following statements is true about energy quantization at the atomic level? electrons in the outermost orbits are the most stable. electrons in all the orbits around the nucleus have the same amount of energy. electrons in the orbit closest to the nucleus have the least amount of energy. electrons absorb or release the same amount of energy independent of the energy levels.