Inorganic Chemistry lacture - 4 “Limit test: Principles, Examples & Easy Explanation”
🧠 Introduction Limit tests are semi-quantitative tests used to check whether the amount of impurity in a substance is within permissible limits or not . 👉 These tests are very important for drug safety and quality control . ⚙️ What is the Principle of Limit Test? 👉 Based on comparison method 👉 Test solution is compared with a standard solution ✔ If test ≤ standard → Pass ✔ If test > standard → Fail 🧪 Limit Test for Chloride 🔬 Principle: Chloride ions react with silver nitrate (AgNO₃) to form silver chloride (AgCl) (white turbidity). 👉 Turbidity of test solution is compared with standard. 🧪 Limit Test for Sulphate 🔬 Principle: Sulphate ions react with barium chloride (BaCl₂) to form barium sulphate (BaSO₄) (white turbidity). 👉 Compared with standard solution. 🧪 Limit Test for Iron 🔬 Principle: Iron reacts with thioglycolic acid → forms purple colored complex . 👉 Color intensity is compared with standard. 🧪 Limit Test for Arsenic 🔬 Principle: Arsenic → conve...
