Chemistry core ideas

Forgotten Chemistry is a user-friendly guide to the major topics of first-year college chemistry. These ideas in simplified form are also the core of the high school chemistry program. The approach used in Forgotten Chemistry is suitable for those who have truly forgotten chemistry and for those who need to refresh their earlier coursework. 

These are core ideas of chemistry, and we will have much more to say about them. 

Key Ideas as Bullet Points The amount of content covered in organic chemistry can be overwhelming to students. To help students focus on the most essential topics, key ideas are emphasized as brrllet points in every section. In preparing bullet points, we have distilled appropriate concepts into simple declarative statements that convey core ideas accurately and clearly. No topic is ever presented as a bullet point if its integrity would be diminished by oversimplification, however. 

The field of supramolecular chemistry has developed at such a rapid pace since the pioneering work of Cram, Lehn, and Pedersen four decades ago that the core ideas of supramolecular chemistry now permeate to adjacent basic and applied scientific fields. In this chapter, we... 

The substance of chemistry as a field of scientific enquiry is made up of four components the processes used to obtain (discover or create) chemical knowledge the general concepts and specific facts so produced the applications of that knowledge in rmderstanding and changing the world and the implications of that understanding and change for individuals and societies. Chemical education involves an introduction to a core of ideas. These ideas are that... 

In short, and as in everything, we need to keep a balance between the temptations of biology and the temptations of materials science. We should certainly show how physical chemistry is relevant to these topics, but not lose sight of the simplicity of the central core of ideas that we are trying to convey. We must educate people into flexibility. 

New ideas for a process A product and a chemical route are defined. This is the phase in which the core of the process is determined. This means that it is already very important to think about the consequences that selecting a certain pathway has on the future final plant and on the plant costs. Choosing a non-optimal pathway may result in a much more expensive final plant design than if another pathway (or, e.g., another solvent or catalyst) were to be chosen. This is the phase in which it is still relatively easy and cheap to make changes that produce the most intensified process. To be able to know the effect of a chemical route on the final plant requires a multidisciplinary team to be involved at this phase, not just chemists, because more aspects play a role than chemistry. This multidisciplinary team should consist of at least chemists and technologists. 

As might be inferred from the word Introduction, the purpose of this book is to teach the basics of the core concepts and methods of computational chemistry. This is a textbook, and no attempt has been made to please every reviewer by dealing with esoteric advanced topics. Some fundamental concepts are the idea of a... 

To make the NEGF-SCF step even more efficient, the restricted MO space idea is proposed. The idea is similar to the scheme of the complete active space (CAS)-SCF method in quantum chemistry [81, 82]. The MOs, whose occupation number should be determined by N EGF-SCF, are the only active MOs, and their energies cover the region dose to EF Vb/2. The inactive MOs, which are core orbitals, are always fully occupied. The MOs of much higher energy than EF are virtual MOs, and their electron occupations are always equal to zero. In typical cases, the applied bias is within a few volts, and the active MOs in the restricted MO space are only about 10% of the MOs in the whole MO space. Note that orbital relaxation is allowed for all MOs because the Hamiltonian is updated. The fixed values in the inactive and virtual MOs are only occupation numbers. 

---