To objects (A and B) of the same temperature are in contact with each other? Which statement is true. A. Heat transfers from object A to object B, because molecules from a collide with those from B.
B. No heat transfers because there are no collisions between the molecules of the objects
C. Heat transfers from object B to object A, because molecules from B collide with those from A
D. Although the molecules collide, no heat transfers because there is no temperature difference between the objects

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.