Li0n
spiKu
Ca(OH)<sub>2</sub> that is, and if so where does it naturally occur? cause i googled everywhere but it just said that its from the industrial burning of limestone with the addition of carbon dioxide and water i think
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is lime a naturally occuring base? (1 Viewer)
- Thread starter Li0n
- Start date
I don't know about Ca(OH)2, I did limestone as in calcium carbonate...this is what I had:
Limestone is a sedimentary rock formed by the compaction of fossilized coral, shells and bones. Limestone is composed of the minerals calcium carbonate (CaCO3) and/or dolomite (CaMg(CO3)2), along with small amounts of other minerals. Calcium carbonate is a source of alkalinity in soils when dissolved in water. This reaction between the calcium carbonate and water occurs when water runs over limestone. The following equations show this:
CaCO3 (s) --> Ca2+ + CO3-
CO3 2- + H2O --> HCO3 - + OH -
The hydroxide ion (OH-) produced is a strong base. The increase in OH - concentration causes the pH to increase. In solution, calcium carbonate has a pH of 8-10.
Hope that helps
Limestone is a sedimentary rock formed by the compaction of fossilized coral, shells and bones. Limestone is composed of the minerals calcium carbonate (CaCO3) and/or dolomite (CaMg(CO3)2), along with small amounts of other minerals. Calcium carbonate is a source of alkalinity in soils when dissolved in water. This reaction between the calcium carbonate and water occurs when water runs over limestone. The following equations show this:
CaCO3 (s) --> Ca2+ + CO3-
CO3 2- + H2O --> HCO3 - + OH -
The hydroxide ion (OH-) produced is a strong base. The increase in OH - concentration causes the pH to increase. In solution, calcium carbonate has a pH of 8-10.
Hope that helps
Li0n
spiKu
Thanks mate 
but for that dot point, are you actually going to talk about your naturally occuring base (limestone in this case) in that much detail?
the dot point only says
" identify data, gather and process information from secondary sources to identify examples of naturally occurring acids and bases and their chemical composition."
So i just thought knowing the chemical formula and the fact that its a naturally occruing acid/base (with an example of where it occurs naturally) is enough.
but for that dot point, are you actually going to talk about your naturally occuring base (limestone in this case) in that much detail?
the dot point only says
" identify data, gather and process information from secondary sources to identify examples of naturally occurring acids and bases and their chemical composition."
So i just thought knowing the chemical formula and the fact that its a naturally occruing acid/base (with an example of where it occurs naturally) is enough.
Xayma
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That second equation should benesstar said:
CO<sub>3(aq)</sub><sup>-2</sup>+H<sub>2</sub>O<sub>(l)</sub> <----> HCO<sub>3(aq)</sub><sup>-</sup>+OH<sub>(aq)</sub><sup>-</sup>
CO<sub>3(aq)</sub><sup>-2</sup> is only a weak base indeed is the conjugate base to a weak acid (or base considering HCO<sub>3(aq)</sub><sup>-</sup> is amphiprotic)
Li0n
spiKu
ah i didnt spot that
I only had it in that much detail cos we did an assessment task on it...I think that we probably only need to know the name and chemical composition, as the dot pt says...and possibly chemical structure
and thanks for the correction Xayma...
and thanks for the correction Xayma...
Li0n
spiKu
ahha i understand now, all you had to say was the word 'assesment'