{"success":true,"version":"v1","request":{"tool":"get_calculator_schema","calculator_id":"mass-percent"},"result":{"entity_type":"calculator","id":"mass-percent","calculator_id":"mass-percent","canonical_url":"https://tttkmbb.com/chemistry/mass-percent","name":"Mass Percent Calculator","title":"Mass Percent Calculator – Solution Concentration as Mass %, ppm and ppb","category":"chemistry","category_name":"Chemistry","tool_name":"calculate_mass_percent","featured_mcp_tool":false,"description":"Computes the mass percent (% w/w) of a solute from the solute mass and either the total solution mass or the solvent mass, and expresses the same concentration as mass fraction, parts per million and parts per billion.","use_when":"You need the % w/w, ppm or ppb concentration of a solute in a solution or mixture from masses.","do_not_use_when":"You need molarity (mol/L, use molarity), the percent composition of an element within a compound (use molar-mass), or volume-based units such as % v/v.","inputs":[{"name":"solute_mass","label":"Solute mass","type":"number","required":true,"exclusive_min":0,"description":"Mass of the solute in any unit shared by all masses (g, kg, mg).","example":5},{"name":"solvent_mass","label":"Solvent mass","type":"number","required":false,"min":0,"description":"Mass of the solvent; solution mass = solute + solvent. 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