... testpositiveSolution appearancecolorlessAssay(dry) %99.0-101.0≥99.0Chlorides,≤ppm50--Heavy metal (lead),≤%105Na, ≤%0.3--Oxalate,≤%0.030.01Sulphates,≤%0.015--Acidity/basicityPass the ... test--Readily carbonizable substancesNot lower than standard--Drying loss,%4.0-7.0≤6pH-value (5% transparent solution)--7.5-9.0As ...