The decreasing acidity of substances C6H5 OH (1), p - CH3 OC6H4 OH (2), p-NO2C6H4OH (3) pCH3COC6H4OH (4), p-CH3C6H4 OH (5) is:

metric time was an attempt to create a standard unit of time based off of 10, but it never took off an is not included in the metric system (si)

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.