Question

What compound is formed by two elements which have `Z=12`, and `Z=9` respectively?

Answer 1

Well, if the these are NEUTRAL atoms, then we gots `"magnesium fluoride."`

Explanation:

......`Z=12`, and `Z=9`, respectively. Why? Because in the neutral atom there are an equal number of protons, positively charged nucular particles, and electrons, negatively charged EXTRA-nuclear particles.

And so a quick glance at the Periodic Table tells us that we got `Mg, Z=12`, and `F, Z=9`, respectively. And since these commonly form dication, and monoanion respectively, by addition or subtraction of electrons, we gots......`MgF_2`.