碳碳碳碳碳，真係搞到我就黎燒碳喇...........

碳酸鹽點解會係鹼性﹖
你FORM 5 未洗學住，你知道佢有2條式﹕
HCO3- + H2O 可逆 CO3 2 - + HCO3+
&
CO32- + H2O 可逆 HCO3- + OH- 穩定D，所以咪鹼性(BASE) 囉。

碳酸氫鹽點解會係鹼性﹖
同上面差唔多，但係佢係兩性﹕
酸﹕ HCO3- + H2O 可逆 CO3 2- + H3O+
鹼﹕ HCO3- + H2O 可逆 H2CO3 + OH- 穩定D，所以咪鹼性(BASE) 囉。

大量二氧化碳從石灰石中的可溶碳酸鹽釋放﹖
係嫁，石灰石係CaCO3，話就話唔溶，其實係微溶 = =
CO3 2- + H2O 可逆 HCO3- + OH-
HCO3- + H2O 可逆 H2CO3 + OH-
H2CO3 可逆 H2O + CO2


大概係咁啦，不過1號係答得好過我的，你捒佢啦，你睇唔明，人地睇得明嗎= =
鬼叫你MaMi DaDi唔爭氣幫你捒間好的幼稚園-->小學-->中學，仲要用英文咩 = =
睇開D啦，依D就係母語教學的偉大喇﹗
話雖如此，有時我地都有我地着數的地方的，不過數啦，執生啦﹗

CO3 2- is the conjugate base of acid HCO3-
the following equilibrium exists:
HCO3- + H2O < - > CO3 2- H3O
since HCO3- is a weak acid, its conjugate base CO3 2- is a strong base and is susceptible to hydrolysis:
CO3 2- + H2O < - >HCO3- OH-
This hydrolysis produces OH- making the solution more basic

For HCO3-.. it is an amphoteric species, i.e it can act as both base and acid
as acid: HCO3- + H2O < - > CO3 2- + H3O (1)
as base: HCO3- + H2O < - > H2CO3 + OH- (2)
since the pKb is smaller than the pKa value, the extent of the equilibrium to the right for (2) is greater than (1), on the whole, more OH- is produced than H3O , making the solution more basic.

limestone is CaCO3, it is very slightly soluble in water
so there is some CO3 2- present in water
in the system the following equilibriums exist:
CO3 2- + H2O < - > HCO3- + OH- (3)
HCO3- + H2O < - > H2CO3 + OH- (4)
H2CO3 < - > H2O + CO2 (5)
The solution then contain all these species and can give out CO2.

n.b. On addition of acid, the eqm position of all of the eqm (3),(4),(5) shifts to the right and more CO2 is produced.
Also, the solubility of CaCO3 also increases as the equilibrium
CaCO3(s) + aq < - > Ca2 (aq) + CO3 2- (aq) shifts to the right as CO3 2- is removed by forming HCO3- salt and etc..

2008-03-22 16:52:20 補充：
< - > is the reversible arrow...唔知做咩變左亂碼

2008-03-22 17:21:38 補充：
the H3O should be H3O+