Frequently Asked Question

Quantitative analysis deals with the determination of the amount of analyte in a sample. It is broadly classified into two methods:

1. Gravimetric analysis: This method involves the conversion of the analyte into a weighable form and then determining the mass of the analyte from the mass of the weighable form.

2. Volumetric analysis: This method involves the reaction of the analyte with a reagent of known concentration, and then calculating the amount of analyte from the volume of the reagent used and the concentration of the reagent. There are various types of volumetric analysis such as:

- Titration: This is a technique in which a solution of known concentration (the titrant) is added to a solution of unknown concentration (the analyte) until the reaction between the two solutions is complete.

- Acid-base titration: This is a titration in which an acid and a base react to form a salt and water.

- Redox titration: This is a titration in which an oxidizing agent and a reducing agent react to exchange electrons.

- Complexometric titration: This is a titration in which a metal ion and a ligand react to form a complex ion.

- Precipitation titration: This is a titration in which a soluble salt and a precipitating agent react to form an insoluble precipitate.

Quantitative analysis of Pb(NO3)2 can be carried out using any of the above methods depending on the specific requirements and the availability of resources. Here are some examples:

- Gravimetric analysis: Pb(NO3)2 can be converted to PbSO4 by reacting it with sulfuric acid. The PbSO4 can then be filtered, washed, dried, and weighed to determine the amount of Pb(NO3)2 in the sample. However this technique is not very sensitive for lead determination since the solubility of PbSO4 is rather high.

- Volumetric analysis: Pb(NO3)2 can be titrated with a solution of EDTA (ethylenediaminetetraacetic acid) using xylenol orange as an indicator. The EDTA will react with the Pb(NO3)2 to form a complex ion, and the equivalence point will be reached when all of the Pb(NO3)2 has reacted with the EDTA. The concentration of Pb(NO3)2 in the sample can then be calculated from the volume of EDTA used and the concentration of the EDTA solution. This method can provide very good sensitivity and accuracy for lead determination provided that the concentration of lead is not too low.

The choice of method for quantitative analysis of Pb(NO3)2 will depend on various factors such as the accuracy, sensitivity, selectivity, cost, and availability of equipment and reagents. It is important to select the most appropriate method for the specific application and to ensure that the analysis is carried out carefully and accurately.