Aphysical property can be observed or measured without changing the identity of a substance. which of these choices describes a physical property?

the temperature at which a liquid will boil.

the tendency of a substance to explode.

the tendency of a metal to rust or not rust.

the way the substance reacts with water.

a corroding iron, if that's one of your choices

plasma - state of matter made up of electrically charged particles

the seeing the electronic configuration we can say that the element is fluorine.

fluorine is the most electronegative element in the periodic table.

but by only seeing the configuration we cannot say about its reactivity because we don't know if its configuration after excitation or by addition of electrons.

but if not then, it is the lightest halogen and exists as a highly toxic pale yellow diatomic gas at standard conditions. as the most electronegative element, it is extremely reactive: almost all other elements, including some noble gases, form compounds with fluorine.