{"uid":"cap_xgwYEOqSIwEjzjpmEEsHQ","slug":"chemeq-limiting-reagent-calculator-5c6b056f","name":"ChemEq Limiting Reagent Calculator","description":"Given a reaction and the supplied amount of every reactant, identify the limiting reagent and compute leftover reactant and theoretical product yields.","url":"https://chemeq.openverbs.com/v1/limiting","method":"POST","headers":{},"bodySchema":{"type":"object","$schema":"https://json-schema.org/draft/2020-12/schema","required":["input"],"properties":{"input":{"type":"object","required":["type","method","bodyType","body"],"properties":{"body":{"type":"object","required":["equation","amounts"],"properties":{"amounts":{"type":"array","items":{"type":"object","required":["species","amount"],"properties":{"unit":{"enum":["mol","g"],"type":"string","description":"Default \"mol\"."},"amount":{"type":"number"},"species":{"type":"string","minLength":1}},"additionalProperties":false},"minItems":1,"description":"Supplied amount of every reactant."},"equation":{"type":"string","minLength":1,"description":"Reaction, e.g. \"N2 + H2 -> NH3\"."}},"additionalProperties":false},"type":{"type":"string","const":"http"},"method":{"enum":["POST"],"type":"string"},"bodyType":{"enum":["json","form-data","text"],"type":"string"}},"additionalProperties":false}}},"responseSchema":null,"example":null,"exampleRequest":null,"tags":["x402"],"displayCostAmount":"0.004","displayCostAsset":"USDC","priceDynamic":false,"priceHint":null,"priceStatus":"priced","priceSource":"probe","requiresHandshake":false,"reviewCount":0,"rating":{"score":"0.00","successRate":"0.00","reviews":0,"stars":null,"state":"unrated"},"availabilityStatus":"unknown","priceObserved":null,"sessionDeposit":null,"pricing":{"kind":"static","summary":"$0.004/call","primary":{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.004","per":"call","confidence":"exact"},"accepted":[{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.004","per":"call","confidence":"exact"}]},"paymentMethods":[{"uid":"pm_soRInow04XifYfqc_qZfq","protocol":"x402","methodType":"crypto","chain":"base","mode":"charge","costAmount":"0.004","costPer":"request","priority":0,"asset":"0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913","unit":"request","depositMicros":null,"planRef":null}],"brandName":null,"brandSlug":null,"brandBaseUrl":null,"brandDocsUrl":null,"whatItDoes":"Given a chemical reaction equation and supplied amounts of all reactants, identifies the limiting reagent and computes leftover amounts of excess reactants plus theoretical product yields.","exampleAgentPrompt":"I have 5 mol of N2 and 12 mol of H2 reacting in N2 + 3H2 -> 2NH3 — which is the limiting reagent, how much excess reactant is left over, and what's the theoretical yield of NH3?","exampleUseCases":[{"title":"Lab synthesis yield planning","prompt":"I'm doing a lab synthesis with 2.5 g of H2 and 20 g of O2 reacting as 2H2 + O2 -> 2H2O — can you tell me which reagent is limiting, how much of the other is left over, and the theoretical yield of water in grams?"},{"title":"Haber process production estimate","prompt":"For the Haber process reaction N2 + 3H2 -> 2NH3, I have 10 mol of N2 and 25 mol of H2 — find the limiting reagent and tell me the maximum amount of ammonia I can theoretically produce."},{"title":"Combustion reaction excess oxygen check","prompt":"If I'm burning methane as CH4 + 2O2 -> CO2 + 2H2O with 3 mol of CH4 and 8 mol of O2, which reactant limits the reaction, how much O2 is left unused, and what are the theoretical yields of CO2 and H2O?"}],"resultDescription":"Returns the identified limiting reagent, the remaining (leftover) amount of each excess reactant after the reaction is complete, and the theoretical maximum yield of each product species, typically expressed in moles or grams consistent with the input units.","failureModes":["Unbalanceable or invalid equation string causes a parse error","Amounts array missing a required reactant species returns a validation error","Non-positive or zero amounts may cause computation errors","Specifying an unknown or misspelled chemical species returns an error","Providing amounts in inconsistent units without specifying unit field may default to mol unexpectedly"],"whenToPreferThis":"Choose this endpoint when you need to determine which reactant is limiting in a given chemical reaction and want quantitative results for leftover reactants and theoretical product yields. Prefer this over a general stoichiometry endpoint when the specific task is limiting-reagent identification given full reactant quantities. Use the sibling stoichiometry endpoint instead if you only know the amount of one species and want to find amounts of another.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-09-14T18:30:24.221Z","isFirstParty":false}