why it is taken 85ml of hcl for 1 lt of solvent according to I.P. while it is 43.02ml of hcl when it is calculated?

To better understand the discrepancy between the two values, let's break down the context:

1. Calculation of 43.02 mL of HCl: This calculation is likely based on the molarity or concentration of HCl that needs to be prepared. Molarity is defined as the amount of solute (in this case, HCl) present in a given volume of solvent (in this case, 1 L). By performing the necessary calculations, one would determine that 43.02 mL of HCl is required to achieve the desired concentration.

2. IP (Indian Pharmacopoeia) guidelines for 85 mL of HCl: The Indian Pharmacopoeia is a set of standards and guidelines for the quality and safety of drugs and pharmaceutical products in India. The mentioned 85 mL of HCl may be a specific requirement stated in the IP for a particular preparation or test. It is important to note that these guidelines could be based on factors such as specific experimental conditions, desired results, or safety considerations.

Therefore, the difference between the two values is likely due to different contexts: one being a calculation based on molarity, and the other being a guideline or requirement specified in the IP. It is essential to consider the relevance and specific context of each value when determining the appropriate amount of HCl to be used.