Quantitative Determination of Sulphate by Gravimetric Analysis
CP4001: ANALYTICAL & PHYSICAL CHEMISTRY | | Formal Report of the Quantitative Determination of Sulphate by Gravimetric Analysis (Experiment 4) | Maryjo Lee Wei Min 1111107 DBS/FT/1A/01 |
(A) Synopsis
The amount of sulphate is determined quantitatively as barium sulphate by gravimetric analysis. This determination consists of slowly adding a dilute solution of barium chloride to a hot, unknown sulphate solution which is slightly acidified with concentrated hydrochloric acid. A white precipitate will formed and is then filtered off, washed with deionised water, dried in the oven and weighed as barium sulphate. The percentage of sulphate is calculated from the weight of barium sulphate.
(B) Objective
The purpose of the experiment is to quantitatively determine the amount of sulphate, in barium sulphate, by the gravimetric method.
(C) Theory
Gravimetric analysis gets its name from the process of isolating the desired constituent in weighable form. In summary, it involves changing one compound containing the constituent into another compound containing that constituent and measuring the percentage of sulphate in the new compound to determine the percentage of sulphate in the previous compound. This experiment also demonstrates the concept of stoichiometry. Stoichiometry is the determination of the proportions in which chemical elements combine and the mass relations in any chemical reaction.
Also known as mass analysis, gravimetric analysis is used to determine an analyte by selective precipitation of the substance from an aqueous solution. The analyte, in this case, is sulphate. For a successful gravimetric analysis, barium sulphate must be completely precipitated so as to avoid contamination. The number of moles of sulphate can be found out from the mass of the barium sulphate. Since barium chloride is added in excess, and since the precipitation reaction is assumed to proceed to completion, we can assume that the number of moles of
(A) Synopsis
The amount of sulphate is determined quantitatively as barium sulphate by gravimetric analysis. This determination consists of slowly adding a dilute solution of barium chloride to a hot, unknown sulphate solution which is slightly acidified with concentrated hydrochloric acid. A white precipitate will formed and is then filtered off, washed with deionised water, dried in the oven and weighed as barium sulphate. The percentage of sulphate is calculated from the weight of barium sulphate.
(B) Objective
The purpose of the experiment is to quantitatively determine the amount of sulphate, in barium sulphate, by the gravimetric method.
(C) Theory
Gravimetric analysis gets its name from the process of isolating the desired constituent in weighable form. In summary, it involves changing one compound containing the constituent into another compound containing that constituent and measuring the percentage of sulphate in the new compound to determine the percentage of sulphate in the previous compound. This experiment also demonstrates the concept of stoichiometry. Stoichiometry is the determination of the proportions in which chemical elements combine and the mass relations in any chemical reaction.
Also known as mass analysis, gravimetric analysis is used to determine an analyte by selective precipitation of the substance from an aqueous solution. The analyte, in this case, is sulphate. For a successful gravimetric analysis, barium sulphate must be completely precipitated so as to avoid contamination. The number of moles of sulphate can be found out from the mass of the barium sulphate. Since barium chloride is added in excess, and since the precipitation reaction is assumed to proceed to completion, we can assume that the number of moles of