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Ca(OH) 2 or CaO · H 2 O: Calcium hydroxide (portlandite) C-S-H: 0.6–2.0 CaO · SiO 2 · 0.9–2.5 H 2 O, with variable composition within this range, and often also incorporating partial substitution of Al for Si: Calcium silicate hydrate: C-A-H: Phase more complex than C-S-H: Calcium aluminate hydrate C-A-S-H: This is even more complex than ...
P 4 + 4 OH − + 4 H 2 O → 4 H 2 PO − 2 + 2 H 2. Any phosphites produced in this step can be selectively precipitated out by treatment with calcium salts. The purified material is then treated with a strong, non-oxidizing acid (often sulfuric acid) to give the free hypophosphorous acid: H 2 PO − 2 + H + → H 3 PO 2. HPA is usually ...
Paper Coating 1) The paper or board 2) The first layer of coating to even out the surface 3) A second layer for an even smoother and whiter surface. Pigments that absorb in the yellow and red part of the visible spectrum can be added. As the dye absorbs light, the brightness of the paper will decrease, unlike the effect of an optical ...
When calcium bisulfite is digested as a food additive, different reactions in metabolic pathways can result. One common pathway results in a reaction that will yield 6%-8% sulfur dioxide . This can go to sulfite when absorbed by the lungs, and the sulfite will be converted to sulfate in the liver by an enzyme called sulfite oxidase .
These materials contain Ca 2+ combined with the polyphosphates, such as P 2 O 4− 7 and triphosphate P 3 O 5− 10: Dicalcium diphosphate (CAS#7790-76-3]: Ca 2 P 2 O 7; Calcium triphosphate (CAS# 26158-70-3): Ca 5 (P 3 O 10) 2
Solid HP(O)(OH) 2 has tetrahedral geometry about the central phosphorus atom, with a P−H bond of 132 pm, one P=O double bond of 148 pm and two longer P−OH single bonds of 154 pm. In common with other phosphorus oxides with P−H bonds (e.g. hypophosphorous acid and dialkyl phosphites ), [ 2 ] it exists in equilibrium with an extremely minor ...
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: Ca(OH) 2 → Ca 2+ + 2 OH −. The solubility is affected by the common-ion effect. Its solubility drastically decreases upon addition of hydroxide or calcium sources.
Pozzolanic reaction is a long term reaction, which involves dissolved silicic acid, water and CaO or Ca(OH) 2 or other pozzolans to form a strong cementation matrix. This process is often irreversible. Sufficient amount of free calcium ion and a high pH of 12 and above is needed to initiate and maintain the pozzolanic reaction. [2]