Wednesday, July 27, 2011

Naming Inorganic Compounds



Introduction


The primary control in the chemical tests have to know the identity of the original materials. These data may be communicated by the name of the material and the labels of containers of reagents. The following sections describe the systematic names of simple inorganic compounds. These systematic names can be transferred with the chemical formula, and communicates the name of the chemical formula.


Binary covalent compounds


Covalent compounds can be operationally defined as compounds that do not conduct electricity and clean when in liquid form. These compounds, with few exceptions, composed of a non-metallic components only. Binary covalent compounds are composed of two non-metals, and the name of the compound was built by the chemical formula as follows:


Prefix prefix + name + mother first element second element + ide


Element of the body consists of dropping the last syllable is the name of the item. Prefixes for the number of atoms in every part of the equation, and the prefix corresponding to a given number of atoms can be found in Table 1, the prefix "But" has been dropped with the exception of carbon monoxide, and decided, " IDE "is available any two elements in compounds. Carbon dioxide is a familiar example of a systematic name. The name tells you what elements make up the carbon dioxide, the number of atoms of each element, and then the chemical formula for carbon dioxide. Please note, a compound that appeared on the Internet is dihydrogen oxide, which is the formula of this compound? The following examples may help answer this question.


Example 1 - What is the formula for sulfur hexafluoride?


The components of the composite, S and F. In addition the prefix hexadecimal says there are 6 F atoms, so the formula is SF6.


Example 2 - Name the compound N2O4?


The name is nitrogen tetroxide.

Table 1--Prefixes for number of atoms

Number of atoms
Prefix
1
mon
2
di
3
tri
4
tetra or tetr*
5
penta or pent*
6
hexa or hex*

*The first spelling is used if the stem of the element begins with a consonant and the second spelling if the stem of the element begins with a vowel.


Binary ionic compounds


Ionic compounds are operationally defined as compounds that conduct electricity when clean and in liquid form. All ionic compounds are solid at room temperature and with few exceptions, made of a metal and non-metals. When the metal is an element of Group IA, Group II element, or aluminum, is the name given by the form:


Diocese of non-metallic element + IDE


This system does not use prefixes and assumes knowledge of the law of electrical neutrality, the octet rule, and the ionic theory. Ionic theory states that ionic compounds consist of positive and negative ions formed by transfer of valence electrons between atoms or molecules. The attraction between the obligations of oppositely charged ions, the ions and the solid state. In the liquid state of the electrical attraction is much weaker and the ions are mobile. This explains why ionic compounds conduct electricity in liquid state. Electrical neutrality requires the total charge of positive and negative ions are equal and that no valence electrons are gained or lost by the transfer of electrons between atoms and molecules. The octet rule is used to attribute changes in the ions that form a compound, and said the group IA and IIA and aluminum components lose their valence electrons while nonmetals gain electrons to the total number of electrons valence of eight.


Example 1 - fluorite mineral has the chemical formula CaF2. What is fluorite is a systematic name?


The names of the elements that make up the fluorite


calcium and fluoride.


The last byte of fluoride in the IDE and the change of name is calcium fluoride.


Example 2 - What is the chemical formula for cesium sulfide?


The complex consists of cesium and sulfur. Since the periodic table and the octet rule, we


Cs 1 Valence loses 1 e-mail


S has 6 valence ee-two victories.


For the electrons lost equal electrons gained, two cesium atoms lose electrons we have


2 CS Valance has two e-solutions e-2


S 6 Valance wins e-2 e


and the formula for cesium sulfide Cs2S. Note to compose sulfide ions of cesium is Cs + and S2.


There are many other examples of metallic elements, and these metals are called transition metals (elements in columns headed by a B), inner transition metals (metals in separate block of the periodic table), or post-transition metals (all of the group IIIA - VIA metals except aluminum). A common property of all these metals is the formation of stable ions with different charges depending on the conditions under which the ion is formed. For ionic compounds with metals, the systematic name is:


metal (Roman numerals) non-metallic rods + IDE.


The Roman numeral is equal to the charge of metal ions. The following examples show how the names of these compounds are assigned and used to determine the chemical form of the name.


Example 1 - Color Ruby and Sapphire is a small amount of Cr2O3 in gemstones. What is the systematic name for Cr2O3?


The load on the "B" metal is determined from the non-metallic. In the periodic table and the octet rule


O has 6 valence e-2 wins


and for composites


3 O 18-th and Valencia have won the sixth


As the electrons lost equal electrons gained, said the chemical formula


2 Chron lost E-6


then


Cr lost 3 e.


The name of the compound is chromium (III) oxide.


Example 2 - a lead compound (IV) oxide used in car batteries. What is the chemical formula of lead (IV) oxide?


Pb and lost 4-(lead (IV))


The following examples illustrate the system of nomenclature and chemical principles.


O has 6 valence e-e-2 wins (from speeches and periodicals octet rule)


Lost electrons so the electrons are the same, say two O


Lost 4 e-Pb


O 2 has 12 valence-gain and-4.


The chemical formula is PbO2.


Ionic compounds with polyatomic ion or complex


Polyatomic ion or complex are examples of molecules that have lost or gained valence electrons. The names of ionic compounds the negative ions in the complex ends with "ite" or "eaten", with few exceptions. The most common exceptions are compounds that contain the following complex ions:


Hydroxide ions OH-


CN, cyanide ion


O22-Peroxide ions.


The names of compounds with these ions are composed of metal and anions. For example, the name of the poison sodium cyanide NaCN.


Many complex ions NMOmn formula, and the names of ionic compounds containing these ions are structured this way:


metal and nonmetal auction ite or ate.


The "ate" ion always has one more than the O atom "ite" ion. For example, SO42-is the sulfate ion and sulfite ion SO32-is. For a non-metallic, knowing the charge and the number of oxygen atoms in the "ate" ion is sufficient to recall the formula and a charge to "ite" ion. Table 2 lists six "ate" ions, and these are the best souvenir. The composition of other ions can be deduced from these ions and the periodic law. In writing formulas with complex ions are more complex ions in parentheses, but only complex ions were not in parentheses. A few examples illustrate the names of compounds with complex ions follow.

Example 1--Phosphate rock has the chemical formula Ca3(PO4)2.  What is the systematic name of phosphate rock?

The names of the component elements excluding oxygen are
            calcium phosphorous
and since PO4 is the formula of phosphate ion the name is calcium phosphate.
Example 2--A preservative has the name sodium nitrite.  What is the chemical formula of the preservative?
            Nitrite ion refers to the ion NO2   which has gained 1 e
            Na has 1 valence e  loses 1 e.
Since electrons lost equals electrons gained, the chemical formula is NaNO2.
Example 3--What is the charge on the complex ion in the compound Na2C2O4?
The charge is determined from the "A" metal
            Na has 1 valence e loses 1 e
and since the formula has 2 Na ions, the number of electrons lost is
            2 Na have 2 valence e lose 2 e.
and electrical neutrality requires that
            C2O4n– gains 2 e.
The charge is –2 (C2O42–).

Table 2--Names and formulas of common oxyanions

Ion
Name
CO32–
carbonate ion
NO3
nitrate ion
SiO44–
silicate ion
PO43–
phosphate ion
SO42–
sulfate ion
ClO3
chlorate ion

Acids
             Acids are operationally defined as compounds that form sour tasting solutions, turn blue litmus paper pink, have a pH less than 7, and chemically react with bases to neutralize acid and base properties.  Theoretically acids donate hydrogen ions (H+) and produce hydronium ion (H3O+) in water.  The formulas of these compounds are written with acid hydrogen first.  For example, H2SO4 is the chemical formula of sulfuric acid and indicates two acidic H.  The systematic name of a binary acid, HnX where X is a nonmetal element, is assigned using the format
            Hydro + stem of nonmetal element + ic acid.
The chemical formula of a binary acid can be determined from the name by determining the charge predicted by the octet rule for the nonmetal element and then balancing this charge with the appropriate number of hydrogen ions.  Examples 1 and 2 below illustrate the application of these rules.
            Oxyacids are another common group of acids, and the chemical formulas for these compounds have the form HnNMOm.  The name of an oxyacid has the form
            stem of nonmetal + ous or ic acid.
For a specific nonmetal, the ous acid always has one less oxygen than the ic acid.  The correct ending can be selected by treating the acid as an ionic compound composed of hydrogen ions (H+) and a complex ion, applying electrical neutrality to assign the charge on the complex ion, naming the complex ion, and then changing the ite ending to ous acid or the ate ending to ic acid.  The procedure is reversed to determine the chemical formula from the systematic name.  Also, the system can be extended to less or more oxygens by adding the prefix hypo to the ous acid for one less oxygen and the prefix hyper to the ic acid for one more oxygen.  Examples 3 and 4 illustrate the systematic naming of oxyacids. 
Example 1--H2S is a foul smelling gas that forms an acidic solution when dissolved in water.  What is the acid name of H2S?
The compound is a binary acid and the name is
            hydrosulfuric acid.
Example 2--Hydrofluoric acid is used to etch glass.  What is the chemical formula of  hydrofluoric acid?
The nonmetal is fluorine and the the octet rule predicts
            F has 7 valence e- gains 1 e; F
            H has lost 1 e-; H+
The chemical formula is HF.
Example 3--One of the acids found in acid rain has the chemical formula H2SO3.  What is the name of  this acid?
The acid has two acidic H hence
            2 H have lost 2 e; 2 H+
            SO3 has gained 2 e; SO32-.
The name of the complex ion is sulfite ion, and the name of the acid is sulfurous acid.
Example 4--Carbonic acid is present in all carbonated beverages.  What is the chemical formula of carbonic acid?
The ic ending says the acid may be treated as composed of carbonate ion and hydrogen ion. The corresponding chemical formulas are
            CO32– has gained 2 e
            H+ has lost 1 e,
and electrical neutrality says
            CO32– has gained 2 e
            2 H+ have lost 2 e.
The chemical formula of carbonic acid is H2CO3.


Chemistry 1000 exercise on Inorganic Nomeclature

1.   The correct scientific name for the mineral hematite, Fe2O3, is
      a)iron oxide

      b)iron(III) oxide

      c)diiron trioxide

2.  Please name the following

      a)AsF3

      b)Al2S3

      c)TiO2

      d)CoCl2

      e)Cr(OH)3

3.Please write the formula for

      a)Manganese(III) phosphite

      b)Strontium fluoride

      c)Sodium nitrate

      d)Dinitrogen pentoxide

      e)Potassium carbonate

4.Please write the chemical formula and charge for

      a)  sulfide ion

      b)  sulfate ion



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