What are the types, Definitions, Properties, and Uses of Primary and secondary reference standards?
What are Reference Standards? Solutions of exactly known strength are called standard solutions. A standard solution contains a known weight of chemicals in a definite volume of solution. A standard solution is prepared by dissolving an accurately weighed quantity of highly pure substance in a definite volume of solvent. Types of Standard Solutions There are two types of standard solutions first is primary standard and secondary standard. Primary standard Any reagent or chemical which has all these properties is suitable for use as a primary standard: It is extremely pure. It is highly stable. It is anhydrous. It is less hygroscopic. It has a very high molecular weight. It can be weighed easily. It should be ready to use and available . It should be preferably nontoxic Following is the detail of a few properties Purity: To qualify as being the primary reference standard, a chemical needs to be extremely pure. Preferably...