A nonpolar covalent bond (i.e., pure covalent) would form in which one of the following pairs of atoms?Group of answer choicesNa — Cl   Br — Br              Li — Br            H — Cl

A nonpolar covalent bond forms when two identical atoms share a pair of electrons. The shared pair of electrons is equally attracted to both atoms because they have the same electronegativity.

Looking at the given pairs of atoms:

1. Na — Cl: This is an ionic bond. Sodium (Na) is a metal and Chlorine (Cl) is a non-metal. Metals and non-metals usually form ionic bonds.

2. Br — Br: This is a nonpolar covalent bond. Both atoms are identical, so they have the same electronegativity and the shared pair of electrons is equally attracted to both Bromine atoms.

3. Li — Br: This is an ionic bond. Lithium (Li) is a metal and Bromine (Br) is a non-metal. Metals and non-metals usually form ionic bonds.

4. H — Cl: This is a polar covalent bond. Hydrogen (H) and Chlorine (Cl) are both non-metals, but Chlorine is more electronegative than Hydrogen, so the shared pair of electrons is more attracted to the Chlorine atom.

So, the pair of atoms that would form a nonpolar covalent bond is Br — Br.