Acids polyatomic

Divide constituents into electropo tive and electronegative. This requires decisions concerning compound type. There are special rules for acids, polyatomic groups, binary compounds, chain compounds, intermetaliic compounds, coordination compounds, and addition compounds [q.v.]. Assemble foe formula. 

Sensitivity levels more typical of kinetic studies are of the order of lO molecules cm . A schematic diagram of an apparatus for kinetic LIF measurements is shown in figure C3.I.8. A limitation of this approach is that only relative concentrations are easily measured, in contrast to absorjDtion measurements, which yield absolute concentrations. Another important limitation is that not all molecules have measurable fluorescence, as radiationless transitions can be the dominant decay route for electronic excitation in polyatomic molecules. However, the latter situation can also be an advantage in complex molecules, such as proteins, where a lack of background fluorescence allow s the selective introduction of fluorescent chromophores as probes for kinetic studies. (Tryptophan is the only strongly fluorescent amino acid naturally present in proteins, for instance.)... 

Step 2 If the compound is an oxoacid, derive the name of the acid from the name of the polyatomic ion that it produces, as in Toolbox D.1. In general,... 

In this equation, r) the absolute hardness, is one-half the difference between /, the ionization potential, and A, the electron affinity. The softness, a, is the reciprocal of T]. Values of t) for some molecules and ions are given in Table 8.4. Note that the proton, which is involved in all Brdnsted acid-base reactions, is the hardest acid listed, with t — c (it has no ionization potential). The above equation cannot be applied to anions, because electron affinities cannot be measured for them. Instead, the assumption is made that t) for an anion X is the same as that for the radical Other methods are also needed to apply the treatment to polyatomic... 

Network Polyesters Synthesized with Polyatomic Acid and Polyatomic Alcohol.222... 

NETWORK POLYESTERS SYNTHESIZED WITH POLYATOMIC ACID AND POLYATOMIC ALCOHOL... 

The name of each oxoacid is based on the name of the polyatomic anion from which it forms, followed by the word acid. Review Table for the names of common polyatomic anions. 

An oxoacid that forms from a polyatomic anion whose name ends in -ate has a name ending in -ic. For example, HNO3 forms by adding a proton to the nitrate polyatomic anion, so HNO3 is nitric acid. Likewise, HCIO4 is perchloric acid from the perchlorate anion. 

Other acids are made up of more than two elements and often contain polyatomic ions. Polyatomic ions are collections of two or... 

There are also some polyatomic ions that end with the letters -ite. S032- and N02 are examples of polyatomic ions with -ite endings. The ion S032- is called a sulfite ion and N02 is a nitrite ion. To name an acid that contains a polyatomic ion that ends in -ite, change the -ite to -ous and add the word acid. Therefore, the name for H2SOs is sulfurous acid and HN02 is nitrous acid. 

Sulfuric acid, on the other hand, is made up of the polyatomic sulfate ion, which has a charge of -2. Because it has a charge of -2, a sulfate ion requires two hydrogen ions (each of which have a charge of+1) to make it stable. Therefore, sulfuric acid is made up of two hydrogen ions and one sulfate ion, and its chemical formula is H2S04. The subscript number two after the symbol for hydrogen... 

Because the cation characteristic of the solvent is IF4+, it is reasonable to assume that the ion may have some existence in other situations. As with the other polyatomic ions shown so far, the reaction selected involves a strong Lewis acid such as SbF5 to remove l , and the same approach is taken for producing C1F4+ and BrF4+ in the interhalogen solvents. 

A cation containing two xenon atoms, Xe2Fu+, is also known, and it has a structure that can be shown as F5Xe+"-F -" XeF5+. Polyatomic anions containing xenon are produced because XeFs is also a Lewis acid. An example of this type of reaction can be shown as... 

See the chart on page 158. Any anion derived from a weak acid acts as a base in a water solution. The carbonate polyatomic anion, C032 laq), is derived from the weak acid carbonic acid, H2C03. There are no common basic cations. 

This fusion method produces an acid-soluble glass bead which is dissolved in nitric acid. It avoids the use of hydrofluoric and perchloric acids. The disadvantages are the cost of platinum labware, and the large quantities of LiB02 used to produce the glass bead increase the total dissolved solids and may contribute to polyatomic species. Dilution to counter these effects may reduce the elements of interest below the instrumental detection limits. 

Crafting names and formulas for ionic and molecular compounds Handling polyatomic ions Talking about acids... 

Binary acids You can easily recognize a binary acid when you see hydrogen bonded to a nonmetallic element or polyatomic ion without oxygen present. 

J 1 Oxy-acids Oxy-acids contain hydrogen bonded to a polyatomic ion containing oxygen. To name a binary acid (no oxygen), use the following steps ... 

Identify the anion for each oxy-acid from the polyatomic ion chart in Table 6-1. If the polyatomic ion ends in -ate, change the ending to -ic. If the polyatomic ion ends in -/Ye, change the ending to -ous. Write acid at the end of the name. (Don t begin with hydro- These aren t binary acids.)... 

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