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Carbonatation is a slow process that occurs in concrete where lime (CaO, or Ca(OH) 2 ) in the cement reacts with carbon dioxide (CO 2) from the air and forms calcium carbonate. The water in the pores of Portland cement concrete is normally alkaline with a pH in the range of 12.5 to 13.5.
Burning (calcination) of calcium carbonate in a lime kiln above 900 °C (1,650 °F) [4] converts it into the highly caustic and reactive material burnt lime, unslaked lime or quicklime (calcium oxide) and, through subsequent addition of water, into the less caustic (but still strongly alkaline) slaked lime or hydrated lime (calcium hydroxide ...
Calcium bicarbonate, also called calcium hydrogencarbonate, has the chemical formula Ca(HCO 3) 2. The term does not refer to a known solid compound; it exists only in aqueous solution containing calcium (Ca 2+), bicarbonate (HCO − 3), and carbonate (CO 2− 3) ions, together with dissolved carbon dioxide (CO 2).
Calcium hydroxide is modestly soluble in water, as seen for many dihydroxides. Its solubility increases from 0.66 g/L at 100 °C to 1.89 g/L at 0 °C. [8] Its solubility product K sp of 5.02 × 10 −6 at 25 °C, [1] its dissociation in water is large enough that its solutions are basic according to the following dissolution reaction:
CaO + H 2 O → Ca(OH) 2 Ca(OH) 2 + CO 2 → CaCO 3 + H 2 O. In a laboratory, calcium carbonate can easily be crystallized from calcium chloride (CaCl 2), by placing an aqueous solution of CaCl 2 in a desiccator alongside ammonium carbonate [NH 4] 2 CO 3. [10] In the desiccator, ammonium carbonate is exposed to air and decomposes into ammonia ...
Montrell Johnson Jr.'s 5-yard touchdown run with 7:40 remaining in the fourth quarter gave Florida a 24-17 win over No. 9 Ole Miss on Saturday in Gainesville. Ole Miss had a chance to tie the game ...
Don't rely on bloviating pundits to tell you who'll prevail on Hollywood's big night. The Huffington Post crunched the stats on every Oscar nominee of the past 30 years to produce a scientific metric for predicting the winners at the 2013 Academy Awards.
A federal judge said Kraft Heinz must face a proposed nationwide class action alleging that it defrauded consumers by claiming its Kraft macaroni and cheese, one of its best-known products ...