How is the Coulombic attraction related to ionization energy across a row?

Ans: Across a row, the nuclear charge increases while the shielding effect of the inner core remains the same. According to Coulomb's law, increasing nuclear charge creates a greater force, so the valence electrons are held more tightly. The greater the ionization energy, the more difficult it is to remove an electron.

Explanation:

the correct answer is:

a. formation of precipitation