The first ionization energy of an element is the energy required to remove an electron from a gaseous atom of an element to produce a +1 ion: M(g) + energy ---> M ^(+) (g) + e -
How do you think the activity of an element ought to be related to its first ionization energy? Predict a decreasing order of reactivity of the above elements based on their first ionization energies.

The higher the ionization energy, the lower the reactivity.

Explanation:

Hello there!

In this case, according to the given information, it turns out possible for us to draw a conclusion about the relationship between ionization energy and reactivity, by bearing to mind that the former is the energy the atom needs to lose its electron, this means that the higher the energy, the more difficult is for the atom to do so.

Based on the aforementioned, since the reactivity is related to how likely an atom undergoes a chemical change by losing or gaining electrons, we can say that the reactivity decreases as the ionization energy increase as, again, it is more difficult for the atom to have an excited state allowing its chemical interaction with another substance.

Unfortunately, the "above elements" where not given, so this part could not be solved, however, you can use the attached periodic trend for ionization energy to figure out the correct order, by keeping in mind the previous reasoning.

the maximum mass of nh3 is nh3 in grams

a is the correct answer