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Chris 09.04.2016 04:45
A general impression I get from your book is that quantum theory is erroneous.

I read that spectroscopy is used to identify functional group and molecular structure in organic chemistry. And textbooks approach to explain spectroscopy is based on the quantum nature of the molecules. Do you still agree with this approach? Or do you think it's erroneous, too?

student 20.01.2016 06:19
I want to study chemistry

Go ahead! Our best wishes to you

Ian J Miller 18.05.2015 23:09
I confess to having a non-standard view on QM, specifically the wave function, from Euler, is real twice a period, and for the stationary state, I suggest that determines the chemical bond. Amongst other things, it requires action to only to be real in discrete quant of h. In the hydrogen molecule, the number of interactions that create potential wells doubles, which means the frequency of electrons in the bond region doubles. If the action is to remain constant (h per electron) and the frequency doubles, the covalent radius then becomes ao (the Bohr radius)/√2 (37.4185 pm). The simplest way of getting the bond energy is to note that only two new waves are created (because repulsive interactions cannot create stationary waves) and if the frequency is doubled in the bond zone, where there is 1/6 e by linearity, the bond energy now becomes 1/3 the Rydberg energy.. I have put this in an ebook called Guidance Waves.

It's interesting. Thank you for invitation to read your book. It's need time to grasp this idea

joshua 25.10.2014 23:24
What is the best meaning of chemistry?

“Chemistry studies substances and their transformations”. We’re surrounded by subjects made of substances so we’re surrounded by chemistry. Each step aimed to improving or changing some property of object forces us to turn our mind to chemistry. Moreover, we can’t live without water, food and fresh air in a word without chemistry. Thus what is the best meaning of chemistry?

Alex 29.09.2014 10:02
how can one understand the phenomenomical aspect of chemistry

The phenomenological approach in science is the method used for creating the observation phenomenon theory. This theory doesn’t pay attention to the low- level processes. The processes can exist and can be unknown. To some extent this is a simplification but is useful if it gives the right phenomenon description.
Therefore you should check the fundamental description of the phenomenon and follow the author’s intention.

Aaliya 09.08.2012 02:53
i want to know how to calculate the covalent radius of heteroatomic molecule and increasing order of - metalic radius, covalent radius, ionic radius and vanderwall radius.

You can get answer from the book " GENERAL CHEMISTRY. Twenty first century." p.p.103-186. There is pdf-versia of this book on page http://itchem.com/generalchemistrytextbook

Andy Standley 16.04.2012 02:53
In light of the elementary reaction steps that are a better description than a combined reaction, can we assign causality to one of the reagents in a chemical reaction? Is one of the reagents always acting on the other(s) to some extent?

Molecules of different compounds are in unequal states in the mixture. The molecule, which has more weaker bond than other, is a initeator of the reaction. Such molecules create an active particles. For example, we add a water solution of chlorine to the colorless solution of sodium bromide, the NaBr solution becomes orange-red because of the formation of bromine. Thus, we get the reaction:
Cl2+2Br- → 2Cl- +Br2
see more http://itchem.com/chemical_reactions

Oliver James 29.03.2012 03:30
Hi you mentioned something about chemical reactions occuring at normal conditions, but them needing high heat to get a thermal reaction. I may be speaking out of context - not really a chemist -
Can we in fact get a thermal reaction with out having such high temps 4000C?
Can 100C give create a chemical reaction?

Hi, Oliver!
1. There are many different reaction which don’t proceed at ‘normal conditions’ /at room’s temperature/. However, if we create a few active particles from initial compounds, this reaction will proceed and new substances will created. We can create active particles by light, by an electric discharge, by a new compound. The last way is an example of a catalytic reaction. In the book you can found some examples.
Cl2 + H 2 → 2HCl and light
BaCl2 + Na2SO4 → BaSO4↓ + 2NaCl and H2O
2H2+ O2 → 2H2O and electric discharge
Active particles, for example, formed by light, cooperate with initial compounds. More see at http://itchem.ru/kak_protekayut_himicheskie_reakcii
2. The temperature 4000C demolishes molecules of initial compounds. In the reaction 2H2+ O2 → 2H2O oxygen molecules and hydrogen molecules break down to hydrogen atoms and oxygen atoms. Then these atoms react between themselves. It’s other way.

24.02.2011 05:35
Zero-base of the general chemistry course

We think that the zero-base of the general chemistry course should be limited to the explanation of the main chemical phenomena: chemical bonding, chemical structure, chemical reactions, and the chemical and physical properties of substances. We agree that it is important to offer the student the cause-effect connections between these phenomena on the qualitative and semi-quantitative level, all the more that at present these bonds have finally been explained. [See: www.itchem.com.]

All questions that have specific meanings should be done away with. This is in reference to questions that the students do not understand, yet, they make attempts to solve them via calculations.

We agree with points 33 and 34 of the compendium.

In general chemistry (especially in the introductory level) it is best not to touch upon questions concerning nuclear reactions in spite of their political importance. From the viewpoint of general chemistry, if we consider politics, information about chemical and biological warfare would be more logic. However, we think that the course of general chemistry should contain chemistry as a science. Its contents, for better learning, should be limited to the minimum at the expense of excluding the material which is well described in physics textbooks, organic chemistry textbooks, biology textbooks, etc.

As far as mass-changes are concerned, we think this is a very important point. Please see our book entitled How Chemical Bonds Form and Chemical Reactions Proceed (pages 415-420). We are working at this problem.

24.02.2011 05:34
Before changing things, one has to know exactly what to change...

I quite agree with you. We think that experimentally (phenomenologically) and via calculations which are given in our book How Chemical Bonds Form and How chemical reactions Proceed (see www.itchem.com.) one should first of all do away with quantum-chemical explanations of chemical phenomena (including the theory of molecular orbitals, valence bonds, the hybridization of orbitals, and the transition state theory) as being incorrect, not capable of explaining anything, and only mystifying chemistry.

At present, the need for excluding quantum-chemical explanations from the introductory level of general chemistry is supported by the majority of chemistry teachers for many reasons. For example, we, the authors of the book How Chemical Bonds Form and Chemical Reactions Proceed, have proven that quantum-chemical explanations of chemical phenomena actually resemble the ‘clothes of the naked king’ in which chemical phenomena are dressed. The most characteristic quantum-chemical explanations are given in our book. Besides, the book proves that the discovery of the wave properties of particles was simply the result of an experimental mistake, while the results of the Schroedinger equation, which fantastically coincided with the experiment, are explained by the unlimited number of adjustments. The proof can well be understood by high school students.

On the other hand, a large group of foremost scientists working in the sphere of teaching chemistry, first of all, R.I.Gillespi, J.N Spenser, R.S.Moog, think that it is necessary to demystify general chemistry, to take out of it all the quantum-chemical explanations.

We think that, at present, the main chemical phenomena, chemical bonding, qualitatively and semi-quantitatively can be correctly explained on the basis of our system which is detailed in our book. That is, we know what should be changed and how to change it!

As to your suggestion to change the whole of general chemistry, say, in favor of organic chemistry, we support you in this. However, we think that your examples speak to the effect that the basics of chemistry, i.e., chemical bonding and chemical reactions, are usually repeated in the first part of the organic chemistry course. We quite agree with your first remark, and we will consider it in our new version of General Chemistry. We will first of all attempt to clearly explain the regularities of only the main chemical phenomena, and there is no need to show our high educational status.




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