I hope someone can help me answer this queestion:

which of the following does NOT involve the sharing of electrons?

H20, HCl, NaCl, H2 or C6, H12, O6

and why?

The last three compounds you listed do not exist. Among the others, NaCl does not share electrons; the Cl completely takes away one electron from the Na, resulting in a purely electrostatic bond.

thanks drwls,
also i mistakingly put commas inbetween
C6H12O6 (glucose)

No problem! Glucose (C6H12O6) is a compound that involves the sharing of electrons. In glucose, the carbon, hydrogen, and oxygen atoms share electrons to form covalent bonds. Covalent bonds are formed when two atoms share a pair of electrons.

On the other hand, NaCl (sodium chloride) does not involve the sharing of electrons. It forms an ionic bond, where one atom donates electrons to another atom. In NaCl, sodium (Na) donates one electron to chlorine (Cl), resulting in a positively charged sodium ion (Na+) and a negatively charged chloride ion (Cl-). The oppositely charged ions are attracted to each other, creating an ionic bond.

To determine if a compound involves the sharing of electrons or not, you need to consider the type of bond it forms. Covalent bonds involve the sharing of electrons, while ionic bonds involve the transfer of electrons.