Dear Suzie,
Dichlorodifluoromethane (Freon-12) was used primarily as a refrigerant, but was banned from use by the Montreal Protocol designed to restore the depletion of ozone in the polar stratospheric regions of the atmosphere. Although it was useful in part because of its relative inertness, it is capable of many different reactions.
Paraphrasing your statement, the function of all molecules is determined in part by their form. ALL non-nuclear chemistry reactions involve the tendency to find the most stable energetic states of matter. That is usually observed by the exchange or sharing of electrons between atoms to form molecules. Molecules themselves have different types of reactivity with other compounds based on their specific shape.
The chlorofluorocarbons (CFC’s) are generally non-flammable, or not reactive in an oxidation reaction. This makes them very attractive for use in human activities. However, it was found that the UV light in the upper atmosphere could spit off the chlorine and fluorine atoms. Those could then react with ozone, removing it from the atmosphere.
So, the “form” of Freon-12 is that it has two chlorine and two fluorine atoms bonded to a central carbon atom. The bond energy of either the chlorine or the fluorine to the carbon can be overcome (broken) by the energy in UV radiation. The C-Cl bond is weaker than the C-F bond, so it is usually the Chlorine atom that gets separated. One estimate is that every chlorine atom in the stratosphere destroys 100,000 ozone atoms before the chlorine is converted to an unreactive form.
A fairly simple explanation of this process can be obtained here:
https://chem.libretexts.org/Bookshelves/Physical_and_Theoretical_Chemistry_Textbook_Maps/Supplementa...
The physical properties of the compound are similarly determined by its form, primarily by mass, heat capacity and its reactivity with other compounds.
Best regards,
Steven
