The attraction between sodium ions (Na+) and chloride ions (Cl-) forms an ionic bond.

Here's why:

* Ionic bonds occur when one atom (in this case, sodium) loses an electron to become positively charged, and another atom (chlorine) gains that electron to become negatively charged.

* The opposite charges of the ions then attract each other strongly, forming a stable compound (in this case, sodium chloride, NaCl).

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