Proton

{
  "id": "MLC-T-CHM-009607",
  "term": "Proton",
  "field": "Chemistry",
  "definition": "A stable subatomic particle with a positive elementary electric charge, found in the nucleus of every atom. It is a baryon composed of two up quarks and one down quark. The number of protons in an atom's nucleus defines its atomic number and thus its chemical element.",
  "subject": "Physical and Biophysical Chemistry",
  "see_also": [
    "nuclear particle",
    "charge number",
    "protium"
  ],
  "references": [
    "Green Book, 2nd ed., p. 93 (https://goldbook.iupac.org/files/pdf/green_book_2ed.pdf)"
  ],
  "url": "https://mlchart.com/terminology/chemistry/proton/"
}