Students in a chemistry lab measure the time it takes four different 100 ml solutions of varying Densities/thicknesses to pass through a hole in the bottom of a cup. Which of
the following physical properties of the solutions is most likely being measured?

the answer would be c

the objects have the same charge.

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.