That's a great question! While both sodium (Na) and chlorine (Cl) are poisonous in their elemental forms, when combined they form sodium chloride (NaCl), which is common table salt.

This is a classic example of how combining elements can change their properties dramatically. Here's why:

* Sodium is a highly reactive metal that explodes when exposed to water.

* Chlorine is a toxic gas that can be deadly in high concentrations.

However, when sodium and chlorine combine, they form an ionic bond, creating a stable, non-toxic compound. This is a fundamental principle in chemistry: the properties of a compound are different from the properties of its constituent elements.