The atomic number of chlorine is 17. The atomic number of magnesium is 12. What is the formula for magnesium chloride?

Question

Quizplus · Accepted Answer

The atomic number of an element tells us the number of protons in the nucleus of its atoms. Chlorine has 17 protons, while magnesium has 12 protons. In order to form a stable compound, magnesium needs to lose two electrons and chlorine needs to gain one electron. Thus, each magnesium atom will combine with two chlorine atoms to form magnesium chloride, which has the formula MgCl₂.

The Atomic Number of Chlorine Is 17