Calcium is prepared commercially through a specific process involving the heating of lime with aluminum.
Production of Calcium
- Historically: Pure calcium metal was initially produced by electrolysis of anhydrous calcium chloride.
- Current Method: The modern method involves heating lime (calcium oxide) with aluminum.
- Reaction: The reaction results in the production of calcium metal.
Calcium's Reactivity
Calcium is not stable in the presence of air. It reacts with:
- Oxygen: Forms calcium oxide.
- Water Vapour: Forms calcium hydroxide.
- Nitrogen: Forms calcium nitride.
These reactions cause a yellow coating to form on the surface of the metal when exposed to air.
Summary
The primary method of preparing pure calcium metal commercially is by heating lime with aluminum. This process is favored over the older electrolytic method. The metal's reactivity with air components like oxygen, water vapor, and nitrogen results in the formation of oxide, hydroxide, and nitride, giving it a characteristic yellow coating.
