Names in science not just chemistry need to be more descriptive and less retarded. The suffixes also denote what oxidation state the central atom is in. This is the general pattern. I don't know about you, but when I studied chemistry I was required to memorize a list of the most common ions, probably of them, their names, and their charges. Figuring out the logic behind the naming helps a lot. Once you learn about oxidation states, remembering the charge is a piece of cake.
There is an SO5! It's not nearly as common as sulfite and sulfate not by a long shot , so it doesn't necessarily fit into the nice little naming scheme. Edit: Also, just for clarity: the ite and ate don't have a relationship to absolute numbers of oxygens, just a relative amount. How many oxygen atoms an "-ite" represents is going to change depending on the primary atom. Which means you're going to have memorize all of your most common polyatomic ions individually, if your instructor chooses to test on them.
Mine didn't. I took high school chem but it was years prior to taking gen chem and I really got my ass kicked. It is not always the case that the '-ate' ion is the most stable, however—as an example, see the links for chlorine below.
A detailed answer necessitates noting that the nomenclature extends beyond just '-ate' and '-ite'. Most p-block elements that form oxo-anions form a whole series of them, each with the central atom in an oxidation state two away from each neighbor. As noted in the comments to another answer, in addition to the '-ite' and '-ate' suffixes, there are also the 'hypo-' and 'per-' prefixes , where 'hypo-' only is used with '-ite', and 'per-' is only used with '-ate'.
These four combinations are used to span the series of oxo-anions for each element:. For carbon, ' carbonate ' was given preference, per the 'most common' rubric, as the only known oxo-anion. For nitrogen, the use of the prefixes was avoided, for what I assume was the sake of simplicity. I would argue that nitrate and nitrite are both common enough in the natural world that without such a deciding factor there would have been stiff competition for the '-ate' suffix.
Possible irregularities in structure within a series include peroxo-anions at high numbers of bound oxygens e. You can find references to oxo-anions of arsenic , selenium , antimony , and tellurium also links are to the '-ates' , but to my mind, these tend to edge more toward the behavior of oxo-anion-forming metals, which either only have a single appreciably stable oxo-anion chromate , molybdate , tungstate , etc. If you really want to blow your mind, take a look at the polymeric oxo-anions like polyphosphate ; or at the at-present theoretical-only orthocarbonate ; or at iron, for which apparently all three of the known oxo-anions are referred to as ' ferrate '.
Historical naming conventions dictate that the "-ate" suffix refers to the group containing the cation with a higher oxidation state than that in the corresponding group designated with the "-ite" suffix. And so on. Sign up to join this community. The nomenclature, or naming, of ionic compounds is based on the names of the component ions.
Here are the principal naming conventions for ionic compounds, along with examples to show how they are used:. Roman Numerals A Roman numeral in parentheses, preceded by the name of the element, is used for elements that can form more than one positive ion. This is usually seen with transition metals. These endings are added to the Latin name of the element e.
Some metals form positive ions in more than one oxidation state. One of the earliest methods of distinguishing between these ions used the suffixes -ous and -ic added to the Latin name of the element to represent the lower and higher oxidation states, respectively.
Chemists now use a simpler method, in which the charge on the ion is indicated by a Roman numeral in parentheses immediately after the name of the element. Negative ions that consist of a single atom are named by adding the suffix -ide to the stem of the name of the element. Predict the formula of the compound that forms when magnesium metal reacts with nitrogen to form magnesium nitride. Click here to check your answer to Practice Problem 4. At first glance, the nomenclature of the polyatomic negative ions in the table above seems hopeless.
There are several general rules, however, that can bring some order out of this apparent chaos. The name of the ion usually ends in either -ite or -ate. The -ite ending indicates a low oxidation state.
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