Why if fluorine the most reactive non metal?

Fluorine is the most reactive of the halogens because it is at the top of the halogen group, which is the second to right group on the periodic table. With halogens, the higher an element is in the column, the more reactive it is. Halogens are reactive because the outer shells that orbit the nucleus lack electrons.

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explanation:

no, the red giant is the hottest with 2.00.000.000 degrees celsius. while the white dwarf only 25,000 degrees celsius.