Which of the following compounds would you expect to conduct electricity when
dissolved in water?
answer choices are:
NaF because it is a covalent compound
NaF because it is a ionic compound
CH4 because it is an ionic compound
CH4 because it is a covalent compoud

B; NaF because it is a ionic compound

Explanation:

First off, just looking at A and C, you can eliminate them because they are inherently false statements:

A) NaF is not covalent; it is ionic because it is made up of a metal (Na) and a nonmetal (F)

C) CH4 is not ionic; it is covalent because it is solely made up of nonmetals (C and H)

Now, a property of ionic compounds is that when they are either molten (melted) or dissolved, they melt in water. Covalent compounds are NOT good conductors of electricity.

Thus, B (NaF because it is a ionic compound) is the answer.

"among the transition metal elements, manganese and zinc have a slight lowering of electronegativities. the reason behind this is that the nuclear charges of these elements are slightly weaker than the other transition metal elements due to the way their valence electrons are filled up. both manganese and zinc have their valence electrons filled up to the 4th shell with 1 pair of electrons (4s2) completely occupying it. although the electrons in the 3rd shell (3d) are yet to be paired since the outer most shell is filled up, the ability of the nucleus to attract electrons is lessened. hence,   the electronegativity (or the ability to attract electrons) is lessened."