Reactivity is not a physical property because it's a characteristic of a chemical element or compound and is involved in chemical process.
Answer:
is the oxidizing agent
Explanation:
An oxidizing agent is an element in a reaction that accepts the electrons of another element. It is typically hydrogen, oxide, or any halogen. In this case, it is oxygen. The answer is 02.
They are the basic components of life or the basic building blocks of life
Ba stays as Ba+2 and Cl stays as Cl-