Hydrogen carbonate ion HCO

Carbon dioxide, C02, and its derivatives, the carbonates, are already familiar to the reader it should be pointed out that the basicities of both the carbonate ion, CO3", and the hydrogen carbonate ion, HCO ", preclude formation of the carbonates of metals whose ions are decidedly acidic thus, neither carbonates nor bicarbonates of Al3+, Cr3+, or Fe3+ have been reported. 

Carbon dioxide, produced by oxidation of substances in the tissues, is carried by the blood to the lungs. Part of it is in solution as carbonic acid, and part as hydrogen carbonate ion, HCO -. If the pH of the blood is 7.4, what fraction is carried as the ion ... 

Write the acid ionization equation and ionization constant expression for the hydrogen carbonate ion (HCO ). 

Rainwater is naturally acidic, with a pH range of 5 to 6, and can become more acidic when it comes into contact with decaying plant matter. Because carbonate ion is the conjugate base of the weak add, hydrogen carbonate ion (HCOs, it readily combines with hydrogen ion. 

The acid is diprotic with a base such as sodium hydroxide it may form both a normal salt, Na2C0.3, and an acid salt, NaHCOs. The normal salt contains the carbonate ion, CO3—, and the acid salt contains the hydrogen carbonate ion, HCOs. ... 

The process can be carried out by running a solution of ammonium nitrate into the nuclear reactor, where it is exposed to neutrons. The carbon that is made in this way is in the form of the hydrogen carbonate ion, HCO.3", and it can be precipitated as barium carbonate by adding barium hydroxide solution. The samples of radioactive carbon are very strongly radioactive, containing as much as 5% of the radioactive isotope. 

Carbonic acid is in equilibrium with the hydrogen carbonate ion, HCOs , which is in turn in equilibrium with the carbonate ion, CO. Each equilibrium has an associated acid-ionization constant. For the loss of the first proton. 

Left Calcium hydroxide solution with bromthymol-blue indicator. Center Carbon dioxide from dry ice reacts with calcium ion to precipitate calcium carbonate. Right In an excess of carbon dioxide,the calcium carbonate dissolves to form a solution of calcium ion and hydrogen carbonate ion, HCOs". In this acidic solution, bromthymol blue changes to a yellow color. 

Example 13 Calculate the basic ionization constant of bicarbonate (hydrogen carbonate) ion, HCO . 

Carbonic acid is diprotic it has two protons, which may dissociate from the parent molecule. Thus there are two dissociation constants, the first one for the dissociation into the bicarbonate (also called hydrogen carbonate) ion HCOs ... 

Carbonic acid (H2CO3) Hydrogen carbonate ion (HCOs ) 4.4 X 10-5 6.36... 

Abnormal electrolyte concentrations in blood serum can indicate the presence of disease. The ion concentrations that vary as a result of disease are Na+, K+, Cl , and HCO J. Sodium ion concentration is a good indicator of the water balance between blood and tissue cells. Unusual potassium ion levels can indicate kidney or gastrointestinal problems. Chloride ion is the anion that balances the positive charge of the sodium ion in the fluid outside the cells. It also diffuses into a cell to maintain normal electrolyte balance when hydrogen carbonate ions diffuse out of the cell into the blood. Table IB shows medical conditions associated with electrolyte imbalances. 

The equations that represent the reactions with water support the prediction that NH4NO3 dissolves to form an acidic solution and Na3P04 dissolves to form a basic solution. Calcium chloride is the salt of a strong base-strong acid, so neither ion reacts with water and the solution is neutral. Both ions in ammonium hydrogen carbonate react with water. Because Kt, for HCOs" is greater than for NH4, the salt dissolves to form a weakly basic solution. 

An important function of the secreted H"" ions is to promote HCOs resorption (top right). Hydrogen carbonate, the most important buffering base in the blood, passes into the primary urine quantitatively, like all ions. In the primary urine, HCOa reacts with H"" ions to form water and CO2, which returns by free diffusion to the tubule cells and from there into the blood. In this way, the kidneys also influence the C02/HC03 buffering balance in the plasma. 

Carbonic acid in aqueous solutions dissociates to form the bicarbonate ion (hCO and a hydrogen ion (H+). 

Setup (a) Chlorine, bromine, and iodine (members of group 7A) all form analogous series of oxoanions with one to four oxygen atoms. Thus, the reference oxoanion is bromate (BrO J), which is analogous to chlorate (CIO J). In parts (b) and (c), HCO J and H2CO3 have one and two more hydrogens, respectively, than the carbonate ion (CO ). 

A central metal ion usually has a pronounced effect on the reactivity of a coordinated ligand at the coordinated atom or atoms. An important reaction of this type which has synthetic value is the reaction of alkenes and alkynes with hydrogen and carbon monoxide in the presence of a metal carbonyl. This is actually the catalytic process of hydroformylation and, although catalysis is beyond the scope of this work, it is nevertheless of interest from the standpoint of ligand reactivity. The reaction of ethylene with hydrogen and carbon monoxide in the presence of HCo(CO)4 as a catalyst is proposed to proceed (at least formally) through the steps shown 1U13) ... 

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