It is a colorless, fuming liquid at room temperature. It is a powerful oxidizer and is used as a rocket propellant, a component of nitric acid production, and as a reagent in organic chemistry.

Here's a breakdown of its properties:

* Color: Colorless at room temperature

* State: Liquid at room temperature

* Odor: Pungent, irritating

* Toxicity: Highly toxic and corrosive

* Reactivity: Powerful oxidizer, reacts violently with many substances

It's important to note that N2O4 is a dangerous chemical and should only be handled by trained professionals.