Number-distribution function

{
  "id": "MLC-T-CHM-008163",
  "term": "Number-distribution function",
  "field": "Chemistry",
  "definition": "A distribution function that gives the relative amount of a substance having a given value of a variable, such as molar mass or degree of polymerization, expressed as mole fraction, so each value is weighted by the number of molecules that have it. It describes the heterogeneity of a polymer sample. Normalized this way, its integral over all values equals 1, and the number-average molar mass is its first moment.",
  "subject": "Polymer",
  "see_also": [
    "amount fraction",
    "variable"
  ],
  "references": [
    "Purple Book, 1st ed., p. 56 (http://old.iupac.org/publications/books/author/metanomski.html)"
  ],
  "url": "https://mlchart.com/terminology/chemistry/number-distribution-function/"
}