H2: The Hydrogen Molecule
Two hydrogen atoms share an electron pair in a sigma covalent bond to form H2, the simplest and most abundant molecule in the universe; bond length, bond energy, and its role as a fuel are stated as real testable numbers.
One proton anchors a single hydrogen atom One electron loops around it, holding steady Two hydrogen atoms drift until they meet Two electrons pair into a single orbital Spins point opposite, orbitals overlap and merge A sigma bond forms where the two shells collide Bond length settles near seventy four picometers Four hundred thirty six kilojoules per mole holds it fast H two, the simplest molecule that exists Colorless, odorless, lighter than the air around it Three quarters of the universe, by mass, is this element Burning at the core of every star you count Rocket engines drink it for a violent thrust Fuel cells split it back apart to make a spark One bond, two nuclei, one shared electron pair Diatomic, stable, quietly complete H two, holding steady, holding tight
Key Concepts: Two hydrogen atoms (1 proton, 1 electron each) share an electron pair, forming a covalent sigma bond | Real bond length (~74 pm) and bond dissociation energy (~436 kJ/mol) | Hydrogen is roughly 75% of the universe's mass | H2 is used as rocket fuel and in fuel cells | Companion to "Hydro Meets Hydro" — same bonding concept, real chemistry vocabulary
Key Words: proton, electron, sigma bond, covalent, bond length, bond energy, diatomic, H2