on dissolving in water CO2 forms H2CO3. why hasnt the huge amt. of co2 dissolved in ocean water form h2co3?

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  • 1 decade ago
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    CO2 and H2O are more stable than H2CO3.

    The natural reaction (without extra energy and catalysts) is H2CO3 produces CO2 and H2O

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  • Som™
    Lv 6
    1 decade ago

    Carbon dioxide dissolved in water is in equilibrium with carbonic acid:

    CO2 + H2O ---> H2CO3

    The equilibrium constant at 25°C is Kh= 1.70×10−3: hence, the majority of the carbon dioxide is not converted into carbonic acid and stays as CO2 molecules. In the absence of a catalyst, the equilibrium is reached quite slowly. The rate constants are :

    0.039 s^−1 for the forward reaction (CO2 + H2O → H2CO3) and

    23 s^−1 for the reverse reaction (H2CO3 → CO2 + H2O).

    From the above equilibrium data its clear that huge amt. of CO2 dissolved in ocean water DOESN'T form H2CO3..... it just remains DISSOLVED AS DOES ANY OTHER GAS like OXYGEN

    Source(s): me
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  • 1 decade ago

    CO2 has limited solubility in water to begin with. Add to that the impact of what is called "common ion effect" and seawater will hold very little CO2. You can demonstrate the common ion effect yourself by taking some club soda and adding just a grain or two of salt. Club soda is plain water that has dissolved CO2 in it. When the salt crystal is added,the NaCl goes into solution and competes with the solubility of the CO2. The result is that the CO2 bubbles off.

    Note, this common ion effect only works with dissolved ionic species, like sodium choride. It will not work with species that are not dissolved as ions, for example sugar.

    Try it...it will suprise you.

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  • 1 decade ago

    Elevated atmospheric CO2 levels HAVE led to increased acidification of the world's oceans, partially through the formation of increasing amounts of carbonic acid (H2CO3). Between 1751 and 2004 surface ocean pH is estimated to have decreased from approximately 8.25 to 8.14 (Jacobson, 2005). This is a big deal, as it fundamentally affects shellfish, corals and other calcifying species.

    While the full effects of these changes in calcification are still uncertain, dramatic changes in the biochemistry of our oceans and all that lives in them over the next 100-200 years can only be avoided with deep reductions in carbon dioxide emissions.

    Source(s): # Jacobson, M. Z. (2005). Studying ocean acidification with conservative, stable numerical schemes for nonequilibrium air-ocean exchange and ocean equilibrium chemistry. J. Geophys. Res. Atm. 110, D07302. # Cicerone, R., J. Orr, P. Brewer et al. (2004). The Ocean in a High CO2 World. Eos. Transactions of the American Geophysical Union 85, 351-353. # Doney, S. C. (2006). The Dangers of Ocean Acidification. Scientific American 294, 58-65.
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  • 1 decade ago

    Basically it has. But H2CO3 is not that stable and will, naturally, decompose and revert back to the H2O and CO2 that is was before. This decomposition is basically that same thing that causes the bubbles in carbonated beverages.

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  • 1 decade ago

    Lancenigo di Villorba (TV), Italy

    Well, I start to examinate your trouble.

    I say you have several chemical compounds in this questions, not only two! Water and carbon dioxide (respectively H2O and CO2) are accompanied by carbonic acid (e.g. H2CO3, present in liquid), oxygen and nitrogen (respectively O2 and N2, present in the air).

    Now, I can define a "chemical system", that is the ensemble of air'gases (CO2 included, air is its source) and underlying oceanic water. In this system you can see two phase's system (one liquid and one gaseous). As you would do it , I assume H2O and H2CO3 present only in liquid phase (its partial pressures are very low at normal conditions thus I can think them as absent in gas phase)...so, in the gas I think are presents only CO2, O2, N2.

    The famous Gibb's rule of chemical equilibrium stated this simple mathematical relationship :

    C.S.V. = C.C.N. + 2 - P.N.

    where C.C.N. is "chemical compound's number", P.N. is "phase's number" and C.S.V. is "chemical system's variance".

    What is "variance"?

    It is the number of physico-chemical parameters which you can decide. Remember! Chemical systems obey to thermodynamics rules who it permit not you decide a number of physico-chemical parameters greater than C.S.V.

    In your case, P.N. is like 2 (one liquid and one gaseous) and C.C.N. is like 4 (H2O, CO2, O2, N2, but not H2CO3 since the latter is colligate to other species by a chemical reaction,

    e.g. CO2 + H2O <-----> H2CO3).

    You can say, now, C.S.V. is like 4. I do an example, you can assign to chemical system its values of temperature, pressure (total pressure), oxygen's partial pressure and carbon dioxide's one. These four values define all other variables by means of thermodynamics relations of chemical equilibria, among these equilibria is the Henry's law. In the past centuries, W. Henry (english chemist) stated that for many gases its concentrations in aqueous solutions are proportional to pressure applied. Nowadays, it is known that it exist a constant's Henry who is function of temperature, pressure and solvent's nature. I advance you that, at normal condition, constant's Henry for CO2 in H2O is like 0.036 mol/(atm*lt) (thirtysix milli-moles of CO2 par one atmosphere of pressure and one liter of water). If you remember that, in same conditions, CO2's partial pressure is not greater than 70 psia (0.05 atm) then you have a former evaluation of H2CO3 (very low) as CO2's containt in the liquid phase.

    I hope this helps you.

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  • 1 decade ago

    because Co2 is not readily dissolves in water. carbondioxide only dissolves in warm water.

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