The strength of an atom's attraction for the electrons in a chemical bond is the atom's?

Yes. An element that is highly electronegative pulls more on the electrons in a bond, such as oxygen in H20. This creates a polar bond, where there is a small negative charge on the oxygen, and a small positive charge in between the hydrogens.

Credit goes to "Erin M" answered on yahoo answers a decade ago.

Ca= 2 ve
Be=2 ve
Mg=2 ve because they are in Group 2a.
 They are slightly less reactive than Group 1a, but more dense that Group 1a.