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A quick Guide On Stoichiometry In Chemical Analysis

Volumetric and Gravimetric Analysis are types of stoichiometric problems that we deal with when we come across the stoichiometry term like volume. The volumetric analysis helps us to understand the relation between the volumes of the given sample whereas the Gravimetric Analysis is used in quantitative analysis. 

Stoichiometry- a  detailed overview

In every chemical equation, there are numbers  written before both the reactant as well as the product that aids in  calculating the amount of the particular substance present in  the given chemical reaction. The chemists and the scientists refer to these terms as  stoichiometric coefficients. With the help of stoichiometry ,it becomes simple to comprehend the relationship seen between the reactant and the product and how the stoichiometric value changes when the reaction  proceeds backwards or forward. 

The volumetric analysis as well as the gravimetric analysis uses the stoichiometric terms to determine the results. The quantitative as well as the qualitative analysis of the compounds uses the following terms. 

Mole : Just like the Si unit for mass is Kg, The SI unit for measuring any particle in chemistry is mole. It is the standard unit used for measuring a small as well as the large particle. The short form used for mole is mol. In 1 mole, 6.022×1023 particles are present. The isotope of Carbon 12 was used to conclude the value of 2 moles.

One can say that Avogadro’s number is the same as that of a mole because the calculated value of 1 mole is the same as that of Avogadro’s number. The Avogadro’s number has the same number of particles i.e. 6.022×1023 as that of 1 mole. This value is very useful for carrying out the conversions. For example from moles to grams or vice versa.

Molar mass: The molar mass of any substance is calculated buy understanding  the moles and the mass of the given substance. If  the mass of the given substance is divided  by the number of moles of the substance, the  value obtained is the molar mass of that  particular compound

Gram molecular mass: The mass that is calculated for one mole of the substance in the unit grams is referred to as gram molecular mass. All these types of terms help us to understand the qualitative as well as the quantitative analysis of the substances. 

Types of chemical analysis. 

There are basically two types of chemical analysis in chemistry:

1. Quantitative analysis

2. Qualitative analysis

Both of them are used to determine the quality as well as the quantity of the substance. 

Volumetric Analysis

The volumetric analysis of the substance falls under the category of quantitative analysis of a chemical compound. It is the method used that helps to determine the volume of the substance that it occupies and the volume with which it combines with the other compound present in the reaction. This procedure in layman’s language is known as titration. 

The most common method that is used for the volumetric analysis is Duma’s method which was made by Jean Baptiste and Andre Dumas. It is commonly used in finding out the amount of nitrogen that has combined with other elements that participated in the reaction. 

Other methods include the Kjeldahl method that helps in the determination of nitrogen. 

Gravimetric analysis

The gravimetric analysis is another type of quantitative analysis that is used in a chemical reaction to help to seek the constituent that is needed and to convert it into a substance of known value so that it can be easily separated from the other compounds and weighed easily. The steps that are followed in the gravimetric analysis is :

Preparing the solution that contains the known value of the desired compound separating the desired constituent from the sample weighing the separated  constituent analysing the amount of the separated constituent and noting its relative amount with the other compounds present.

Conclusion

Both quantitative as well as the qualitative analysis of the compound helps in the analytical chemistry to know the relation of the constituents participating in the reaction. 

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Frequently asked questions

Get answers to the most common queries related to the UPSC Examination Preparation.

How many types of chemical analysis are present?

Ans. There are two types of chemical analysis present in analytical chemistry.

Is quantitative and qualitative analysis the same?

Ans. No. They are two different aspects of analytical chemistry.

Is volumetric and gravimetric analysis a part of quantitative analysis?

Ans. Yes. They both belong to quantitative analysis.