{
  "schema": "upg.factor.v1",
  "id": "ptce/calc/percent-strength",
  "exam": [
    "PTCE"
  ],
  "domain": "Order Entry & Processing",
  "title": "Percent strength (w/v, w/w, v/v)",
  "claim": "Percent strength expresses parts of solute per 100 parts of preparation: % w/v = grams per 100 mL; % w/w = grams per 100 g; % v/v = mL per 100 mL. PTCE Order Entry & Processing items expect correct interpretation of which percent form the label or problem states \u2014 do not mix mass and volume bases.",
  "plain": "% w/v = g/100 mL. % w/w = g/100 g. % v/v = mL/100 mL. Match the letters to the units before you calculate.",
  "confidence": 0.9,
  "citations": [
    {
      "authority": "PTCB PTCE Content Outline \u2014 Order Entry & Processing (domain pin)",
      "url": "https://ptcb.org/wp-content/uploads/2025/07/PTCE-Content-Outline.pdf",
      "pin": "Order Entry & Processing \u2014 percent strength / concentrations (domain pin; not a verbatim PDF quote)",
      "retrieved_at": "2026-09-10",
      "quote": "Domain pin only: PTCE Order Entry & Processing covers concentration / percent-strength calculations. Exact outline bullet wording is not reproduced here."
    }
  ],
  "updated_at": "2026-09-10",
  "token_cost_hint": 220,
  "integrity": "practice_only",
  "html": "/factors/ptce/calc/percent-strength",
  "json": "/factors/ptce/calc/percent-strength.json"
}