Color, phase, odor and boiling point are the physical properties. Reactivity with oxygen depends on the chemical nature of object, thus, it is not a physical property. It is a chemical property.
Answer:
Under the earth's surface, rocks melt, metamorphize, and crystalize.
Explanation:
Metamorphic and Igneous rocks are basically dependant on the heat/pressure of the environment under the surface :) Melting, metamorphosing and crystallization all occur under earth's surface.
Answer: B. No, fluorine is always assigned an oxidation number of -1.
Explanation:
I would say C is the most correct.
In D it depends on what water source you're using. Let's say it is a waterfall, then the source of the water (melting ice or a lake) may disappear in the future.
If you're using underwater "windmills" placed in the ocean, then you would expect it to last a while as the ocean will not disappear in the near future.
Your answer is probably
Vaporization point
