limestone 可唔可以變成 metal ?

可以

limestone (CaCO3)
利用熱解
limestone 會變做 CaO + CO2
CaCO3 → CaO + CO2
CO2 係氣體
會離開 CaO
所以我地會得到 CaO
將 CaO 加熱到溶
solid state to molten state
之後用 carbon electrode 電解
cathode 就會出 calcium metal 鈣

http://hk.knowledge.yahoo.com/question/?qid=7007050604517

Cite from www.webelements.com

Calcium metal is readily available commercially and there is no need to make it in the laboratory. Commercially it can be made by the electrolysis of molten calcium chloride, CaCl2.

cathode: Ca2+(l) + 2e- → Ca anode: Cl-(l) → 1/2Cl2 (g) + e-

The calcium chloride is made by the action of hydrochloric acid upon calcium carbonate. Calcium chloride is also a byproduct in the Solway process used to make sodium carbonate.

CaCO3 + 2HCl → CaCl2 + H2O + CO2

Alternatively, and on small scale, calcium can be made through the reduction of CaO with aluminium or of CaCl2 with sodium metal

6CaO + 2Al→ 3Ca + Ca3Al2O6

CaCl2 + 2Na→ Ca + 2NaCl
參考資料:

http://www.webelements.com/webelements/elements/text/Ca/key.html

我認為理論上可以
電解有鈣的礦石在熔熔型態
limestone 係有鈣的

ｌｉｍｅ　ｓｔｏｎｅ係碳酸ca......唔係metal
冇得變做metal嫁