Search results
Results from the WOW.Com Content Network
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 ...
Ca 5 (PO 4) 3 OH + 5 H 2 SO 4 → 3 H 3 PO 4 + 5 CaSO 4 + H 2 O Ca 5 (PO 4) 3 F + 5 H 2 SO 4 → 3 H 3 PO 4 + 5 CaSO 4 + HF. Calcium sulfate (gypsum, CaSO 4) is a by-product, which is removed as phosphogypsum. The hydrogen fluoride (HF) gas is streamed into a wet (water) scrubber producing hydrofluoric acid. In both cases the phosphoric acid ...
Hypophosphoric acid can be prepared by the reaction of red phosphorus with sodium chlorite at room temperature. [2]2 P + 2 NaClO 2 + 2 H 2 O → Na 2 H 2 P 2 O 6 + 2 HCl. A mixture of hypophosphoric acid, phosphorous acid (H 3 PO 3) and phosphoric acid (H 3 PO 4) is produced when white phosphorus oxidises in air when partially immersed in water.
This is done by adding H 2 O, OH −, e −, and/or H + to either side of the reaction until both atoms and charges are balanced. Consider the half reaction below: OH −, H 2 O, and e − can be used to balance the charges and atoms in basic conditions, as long as it is assumed that the reaction is in water.
Dicalcium phosphate is the calcium phosphate with the formula CaHPO 4 and its dihydrate. The "di" prefix in the common name arises because the formation of the HPO 4 2– anion involves the removal of two protons from phosphoric acid, H 3 PO 4.
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.
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 ...