But Cr(VI) is much more toxic and forms compounds that are reasonably soluble in water. Cr(III), an ingredient of many vitamin and nutritional supplements, forms compounds that are not very soluble in water, and it has low toxicity. In the environment, chromium exists primarily in either the Cr(III) or Cr(VI) forms. (b) The Cr(VI) ion is often present in water as the polyatomic ions chromate, \(\) (right).Ĭhromium compounds are widely used in industry, such as for chrome plating, in dye-making, as preservatives, and to prevent corrosion in cooling tower water, as occurred near Hinckley. (a) Erin Brockovich found that Cr(VI), used by PG&E, had contaminated the Hinckley, California, water supply. The other fluoride of tin is SnF 4, which was previously called stannic fluoride but is now named tin(IV) fluoride. This represents the formula SnF 2, which is more properly named tin(II) fluoride. For example, you may see the words stannous fluoride on a tube of toothpaste. Though this naming convention has been largely abandoned by the scientific community, it remains in use by some segments of industry. Out-of-date nomenclature used the suffixes – ic and – ous to designate metals with higher and lower charges, respectively: Iron(III) chloride, FeCl 3, was previously called ferric chloride, and iron(II) chloride, FeCl 2, was known as ferrous chloride. Names of Some Transition Metal Ionic Compounds These two compounds are then unambiguously named iron(II) chloride and iron(III) chloride, respectively. In cases like this, the charge of the metal ion is included as a Roman numeral in parentheses immediately following the metal name. The simplest name, “iron chloride,” will, in this case, be ambiguous, as it does not distinguish between these two compounds. Iron typically exhibits a charge of either 2+ or 3+ (see ), and the two corresponding compound formulas are FeCl 2 and FeCl 3.
For example, consider binary ionic compounds of iron and chlorine.
The charge of the metal ion is determined from the formula of the compound and the charge of the anion. Compounds of these metals with nonmetals are named with the same method as compounds in the first category, except the charge of the metal ion is specified by a Roman numeral in parentheses after the name of the metal. Most of the transition metals can form two or more cations with different charges. Everyday Ionic CompoundsĪdded to “iodized” salt for thyroid healthīaking soda used in cooking (and as antacid)Īnti-caking agent used in powdered productsĬompounds Containing a Metal Ion with a Variable Charge Look at the label or ingredients list on the various products that you use during the next few days, and see if you run into any of those in this table, or find other ionic compounds that you could now name or write as a formula. Some of these compounds, where they are found, and what they are used for are listed in. The rules for organic compounds, in which carbon is the principle element, will be treated in a later chapter on organic chemistry.Įvery day you encounter and use a large number of ionic compounds.
We will limit our attention here to inorganic compounds, compounds that are composed principally of elements other than carbon, and will follow the nomenclature guidelines proposed by IUPAC.
Iron iii sulfide charge how to#
The simplest of these are binary compounds, those containing only two elements, but we will also consider how to name ionic compounds containing polyatomic ions, and one specific, very important class of compounds known as acids (subsequent chapters in this text will focus on these compounds in great detail). This module describes an approach that is used to name simple ionic and molecular compounds, such as NaCl, CaCO 3, and N 2O 4.
Nomenclature, a collection of rules for naming things, is important in science and in many other situations. Derive names for common types of inorganic compounds using a systematic approach.By the end of this module, you will be able to:
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