After wandering in google image with the keyword “guswanto”, I found my Bsc poster that I posted on my blog in 2010. The poster was about my study on the preparation of precipitated calcium carbonate. I evaluated some mineral acids including nitric acid, hydrochloride acid, phosphoric acid, and sulphuric acid on the formation of the calcium carbonate crystal structure. Only nitric acid and hydrochloric acid had the properties to solubilize high amount of Calcium Oxide. After exposed to carbon dioxide gas, the nitric acid solution formed calcium carbonate with rhombohedral structure, while hydrochloride acid solution formed calcium carbonate with spherical structure. Interesting.
I thank my colleagues during my work in the Material Chemistry Lab, Andalas University, Indonesia.