Give an example of why quantity is at the heart of analytical chemistry

The equivalent ratio is the ratio of the stoichiometric numbers of two chemical substances in a reaction. The closer the equivalent ratio is to the integer of Bu Zhengchun, the higher the efficiency of the chemical reaction.

As an example, consider the following chemical reaction:

2h2 + o2 ->2h2o

In this reaction, hydrogen and oxygen are reacted at an equivalent ratio of 2:1. This means that each molecule of hydrogen-type gas needs to react with one molecule of oxygen to produce two molecules of water.

If the equivalent ratio of the reaction is incorrect, the Qingqimo reaction will be limited, resulting in some reactants not reacting completely, or by-products.

For example, if we only supply enough oxygen to react with 1 molecule of hydrogen, the reaction equation becomes:

2h2 + o2 ->h2o2

The equivalent ratio of this reaction is that the hydrogen cannot react completely, producing hydrogen peroxide.

1. Because quantitative analysis is an important task of analytical chemistry, that is, to determine and calculate the content of the substance m;

2. In order to characterize the determination results (content), there is the calculation of the amount of concentration, the calculation of the accuracy of the content, and the calculation of the sensitivity of the detection method.

Therefore, without the problem of quantity, there would be no emergence and development of analytical chemistry.

Because the purpose of analytical chemistry is quantitative analysis. So quantity is at the heart of analytical chemistry;

The first is reflected in the quantification of the analysis results; The second is the quantity embodied in the use, identification and calibration of the measuring instrument.

Question: Give an example of why"amount"It is the core of analytical chemistry.

Because the purpose of analytic science is quantitative analysis. So quantity is at the heart of analytical chemistry;

The quantity, one is reflected in the analysis results or the quantification of Bu Chang; The second is the quantity embodied in the use, identification and calibration of the measuring instrument.

There is a classification in analytical chemistry: quantitative analysis and qualitative analysis, which usually comes first qualitatively, i.e., what kind of properties does a substance have? Then consider the quantitative change in it in a certain process.

When using this substance, both sex and quantity need to be considered, and when sex is known, the quantity is determined. Analytical methods are divided into instrumental analysis, chemical analysis, and mathematical analysis, which are usually used in combination with each otherWhich of these steps in the process does not require quantification.

In other words, almost all scientific research needs to be quantitative, i.e. mathematical! Otherwise, it is impossible to explore deeply. Here's an example:

The theoretical part of the invention of the atomic bomb. When nuclear physics was studied further and Fermi obtained slow neutrons, the decisive question was how to make the neutron density reach a critical level where a chain reaction occurred. That is, mathematical problems that translate into neutron density and nuclear fission cross-sections.

When the fuel to air is just completely combusted, the mass ratio of air to fuel is called the "chemical equivalent ratio".

For hydrocarbon fuel CXHY, the stoichiometric relation:

cxhy+a(o2+

xco2+（y/2）h2o

In this formula: axy 4

Chemical equilibrium equivalence ratio air(O2,N2): cxhy=a:

1 (stiochiometric) is the unit of measurement for the value here.

It's all mol.