1. Reactivity with Oxygen: Iron readily reacts with oxygen in the presence of moisture, forming iron oxide (rust). This is a classic example of corrosion.

2. Ability to form Ions: Iron can lose electrons to form positively charged ions, specifically Fe²⁺ (ferrous) and Fe³⁺ (ferric) ions. This ability to form ions is key to iron's role in many chemical reactions and its ability to form compounds.