GB/T 22650-2008 Determination of total calcium mg content in industrial sodiumhydrate using complexation Titrimetric method. This standard applies to all kinds of industrial sodiumhydrate products. Using a titrant that can form a stable complex with calcium mg ions, the titration endpoint is determined by a suitable indicator or potentiometric method through complexation reaction, and then the total calcium mg content is calculated. The standard specifies the required instruments, such as Burette, etc., and specifies the preparation of reagents. Detailed description of Sample Handling steps, including dissolving of sodiumhydrate samples, masking of interfering ions, etc. Standardized titration operation process, according to this standard, can accurately determine the total content of calcium mg in industrial sodiumhydrate, help product quality control and production process optimization.