Solutes that when dissolved in water totally dissociate into ions and conduct electricity very well are
1. Strong electrolytes
2. Weak electrolytes
3. Nonelectrolytes

your answer would be a. 12.5 kg

c is the answer because when something is left after something evaporates that shows the chemical change.

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.