[Verse 1] Count the protons, that's your number, Z the name-tag pinned to you, Neutrons ride along for mass, add them up — that's A, the true. Same Z, different N, the isotope twins in disguise, Same A, different Z, isobars wearing borrowed size. Same neutron count, different protons — isotones, the quiet cousins, Electron shells hum round the core like satellites in dozens. Chlorine's got two faces, thirty-five and thirty-seven, Weighted by how often each one shows — that's the leaven. [Chorus] Zed for the protons, A for the whole, Neutrons the ballast that steadies the soul, Isotope, isobar, isotone — spin the wheel, Same skin, same weight, or same quiet appeal. Mass turns to binding, the glue none can see, Iron-fifty-six sits at the peak of the tree. [Verse 2] Weigh the nucleus, it's lighter than the sum of its parts, That missing sliver's mass defect — energy born from the start. E equals m c squared, the ledger that binds the crowd, Binding energy per nucleon — plot it, watch it climb loud. Rises past helium, past carbon, past the calcium crest, Peaks at iron-fifty-six, nickel-sixty-two the contest, Then it slides back down through lead, through bismuth's heavy haze, That's why stars stall at iron — no more embers left to raise. [Verse 3] Not every nucleus is steady — walk the band of stability, N over Z climbs as protons crowd, repulsion's the liability. Magic numbers: two, eight, twenty, twenty-eight, fifty, eighty-two, Closed shells like locked vaults, extra steady, extra true. Even-even nuclei nestle tight, odd-odd ones run thin, Alpha spits out helium, beta-minus turns a neutron in, Beta-plus and capture flip a proton back the other way, Gamma sheds the extra light, fission splits the heavyweight, Half-life ticks it down — N equals N-naught, e to the negative lambda t. [Chorus] Zed for the protons, A for the whole, Neutrons the ballast that steadies the soul, Isotope, isobar, isotone — spin the wheel, Same skin, same weight, or same quiet appeal. Mass turns to binding, the glue none can see, Iron-fifty-six sits at the peak of the tree. [Bridge] Big Bang breathed out hydrogen, helium, a whisper of lithium thin, Stars stitched carbon, oxygen, silicon, burned their way to iron's chin. S-process ambles slow, one neutron sipped at a time, R-process roars in neutron-star mergers, gold forged in that collide, P-process starves for protons, cosmic rays crack boron loose from stone, Beryllium, lithium, boron — spallation's leftover bone. Crust and cosmos both obey the Oddo-Harkins creed, Even Z outnumbers odd — abundance follows that seed. Past the heavy shelf, an island may be waiting still, Superheavy shores of stability, calling from beyond the hill. [Outro] Z counts the charge, A counts the freight, Binding holds the balance, decay writes the fate, From the Big Bang's ember to the neutron star's collide, Every element's a story the nucleus can't hide.
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