In the last post, I discussed the Group A, aka the Main Group, elements. The chemical behavior of atoms -- how they react/combine with other atoms in "the environment" -- is determined by the way electrons are configured orbiting about the nucleus. All Main Group elements (with the biochemically relevant exception of hydrogen) share a valence shell (outermost shell) with 8 "vacancies" for electrons. Having a filled valence shell with 8 electrons is the preferred energy state for these atoms -- this is called the Octet Rule -- and these atoms react/combine in order to satisfy this rule. The atoms in each group (or column) contain the number of electrons in the group number, thus Na is in Group IA has 1e, C in Group IV has 4 e's, and Br in Group VII has 7 e's.
The Group IA and IIA elements lose electrons to form cations to meet the Octet Rule when the next lower filled shell now becomes the valence shell. The Group VIA and VIIA elements have mostly filled shells and will gain electrons to completely fill them.
In this installment I'll discuss how different atoms combine to form unique substances called compounds. One type of compound, ionic, will be discussed in detail, and the formation of an ionic compound shall be used to introduce the concept of oxidation state.
The Group IA and IIA elements lose electrons to form cations to meet the Octet Rule when the next lower filled shell now becomes the valence shell. The Group VIA and VIIA elements have mostly filled shells and will gain electrons to completely fill them.
In this installment I'll discuss how different atoms combine to form unique substances called compounds. One type of compound, ionic, will be discussed in detail, and the formation of an ionic compound shall be used to introduce the concept of oxidation state.
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