A & B
Naming of chemical substances begins with the names of the elements. The discoverer of an element has traditionally had the right to name it, and many of the names refer to the element's properties or to geographic locations.
The system used for naming chemical substances depends on the nature of the molecular units making up the compound. These are usually either ions or molecules and different rules apply to each.
It is often necessary to distinguish between compounds in which the same elements are present in different proportions. Chemists have long used Latin and Greek roots to designate numbers within names.
Two-element compounds are usually quite easy to name because most of them follow the systematic rule of adding the suffix -ide to the root name of the second element, which is normally the more "negative" one.
For rather obscure historic reasons, some of them have common names that begin with -bi which, although officially discouraged, are still in wide use for example,
| HCO3– | hydrogen carbonate | bicarbonate |
| HSO4– | hydrogen sulfate | bisulfate |
| HSO3– | hydrogen sulfite | bisulfite |
Most of the cations and anions can combine to form solid compounds that are usually known as salts. The one overriding requirement is that the resulting compound must be electrically neutral: thus the ions Ca2+ and Br – combine only in a 1:2 ratio to form calcium bromide, CaBr2. Because no other simplest formula is possible, there is no need to name it "calcium dibromide".
Since some metallic elements form cations having different positive charges, the names of ionic compounds derived from these elements must contain some indication of the cation charge. The older method uses the suffixes -ous and -ic to denote the lower and higher charges, respectively.
C.
The most common oxygen-containing anions (oxyanions) have names ending in -ate, but if a variant containing a small number of oxygen atoms exists, it takes the suffix -ite.
How many oxygen atoms an "-ite" represents depends on the primary atom. All you get from the -ite/-ate relationship is that -ate has one more O than -ite.
In other words, if you have two ions, the one with more oxygens is 'ate' and the one with less is 'ite'.
source:
Feiyi 2-1a
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