Hydrogen

 The chemical element H is Hydrogen. 🧪

Here's some key information about it:

 * Symbol: H

 * Atomic Number: 1

 * Atomic Mass: \approx 1.008 u

 * Classification: Nonmetal, the lightest and most abundant chemical substance in the universe.

 * State at Standard Temperature and Pressure (STP): Gas (diatomic molecule, \text{H}_2)

Hydrogen is the simplest element, consisting of just one proton and typically one electron. It's a highly flammable gas and plays a crucial role in water (\text{H}_2\text{O}) and virtually all organic molecules.