Question

question 1 of 10
which of the following molecules contains a nonpolar covalent bond?

a. $\ce{h_{2}}$

b. $\ce{hcl}$

c. $\ce{lii}$

d. $\ce{h_{2}o}$

Explanation:

To determine which molecule has a nonpolar covalent bond, we analyze each option:

• Option A ($\boldsymbol{H_2}$): A hydrogen molecule consists of two identical hydrogen atoms. In a covalent bond between two identical atoms, the electrons are shared equally because the atoms have the same electronegativity. This results in a nonpolar covalent bond.
• Option B (HCl): Hydrogen and chlorine have different electronegativities. Chlorine is more electronegative than hydrogen, so the shared electrons are pulled more towards chlorine, creating a polar covalent bond.
• Option C (LiI): Lithium (Li) is a metal and iodine (I) is a non - metal. This is an ionic compound, formed by the transfer of electrons from Li to I, not a covalent bond.
• Option D ($\boldsymbol{H_2O}$): In a water molecule, the O - H bonds are polar covalent bonds because oxygen is more electronegative than hydrogen. Also, the bent molecular geometry of water makes the whole molecule polar.

So, only $H_2$ has a nonpolar covalent bond.

Answer:

A. $H_2$