Which of the following atoms acquires the most negative charge in a covalent bond with hydrogen

A) C

B) Na

C) O

D) S

I believe it would be Oxygen

C) O

Explanation:

The periodic property that explains how atoms acquire the most negative charge in a covalent bond is the electronegativity. This property is the tendency of an atom to attract a pair of electrons.

It means that in a covalent bond, it's more likely to find the electron close to the most electronegative element. So, an element that needs to gain electrons must be a higher electronegativity than those that need to donate. The non-metals has higher electronegativity than the metals.

This property also increases with the decrease of the size of the atom: small atoms can attract better the electrons because the distance of the positive nucleus will be smaller. So the electronegativity increases from left for right in the periods, and from bottom to top in groups.

Oxygen, Sulfur, and Carbon are non-metals, so they have high electronegativities. Oxygen has higher because is more in right and top, so it is the smallest. Then, Oxygen acquires the most negative charge in a covalent bond with hydrogen.