GCSE›Edexcel GCSE Chemistry›Mind mapsQualitative Analysis: Tests for IonsEdexcel GCSE Chemistry: Mind mapStudy pack PDFAlso for this subtopic:Revision notesFlashcardsSubtopic testCover factsFlame testsLithium: redSodium: yellowPotassium: lilacCalcium: orange-redCopper: blue-greenSodium hydroxideCu²⁺: blue precipitateFe²⁺: green precipitateFe³⁺: orange-brown precipitateAl³⁺: white, dissolves in excessCa²⁺: white, insoluble in excessAmmonium and carbonateNH₄⁺: warm with NaOH, ammonia releasedAmmonia turns damp red litmus blueCarbonate: add acid, CO₂ given offCO₂ turns limewater cloudyTests for ionsqualitative analysisLi⁺Na⁺K⁺Cu²⁺Sulfate and halidesSulfate: HCl then barium chlorideSulfate gives white precipitateHalides: nitric acid then silver nitrateCl⁻ white, Br⁻ cream, I⁻ yellowInstrumentsImprove sensitivity, accuracy and speedFlame photometry identifies metal ionsConcentration from a calibration curveExam tipsLithium red, calcium orange-red: easily swappedSay excess NaOH for Al versus CaAcid first removes carbonate false positives