🧪 Limit Test of Calcium(Inorganic Pharmaceutical Chemistry – Practical Guide)
Calcium is an essential element, but excess calcium as an impurity in pharmaceutical substances can affect drug stability, solubility, and quality. That’s why the Limit Test of Calcium is performed to ensure that calcium content remains within pharmacopoeial limits. 📌 Objective of Limit Test of Calcium To detect and control the amount of calcium impurity present in pharmaceutical substances by comparing the test solution with a standard solution. 🧠 Principle Calcium reacts with ammonium oxalate in an alkaline medium to form a white precipitate of calcium oxalate. 👉 The turbidity produced in the test solution should not be more intense than that of the standard solution. 🧫 Chemical Reaction White precipitate of Calcium Oxalate is formed. ⚗️ Apparatus Required Nessler cylinders Measuring cylinder Beakers Glass rod 🧪 Reagents Required Ammonium oxalate solution Dilute ammonia solution Calcium standard solution Distilled water 🧪 Procedure 🔹 Preparation of Test Solution Take the given...