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In chemistry, a silicic acid (/ s ɪ ˈ l ɪ s ɪ k /) is any chemical compound containing the element silicon attached to oxide (=O) and hydroxyl (−OH) groups, with the general formula [H 2x SiO x+2] n or, equivalently, [SiO x (OH) 4−2x] n. [1] [2] Orthosilicic acid is a representative example.
2009 silicic acid concentration in the upper pelagic zone. [ 19 ] Dissolved silica (DSi) is a term used in the field of oceanography to describe the form of water-soluble silica , which is assumed to be Si(OH) 4 (orthosilicic acid) or its conjugate bases (orthosilicate anions) such as − O−Si(OH) 3 and ( − O−) 2 Si(OH) 2 .
Tetraethyl orthosilicate, formally named tetraethoxysilane (TEOS), ethyl silicate is the organic chemical compound with the formula Si(OC 2 H 5) 4. TEOS is a colorless liquid. It degrades in water. TEOS is the ethyl ester of orthosilicic acid, Si(OH) 4. It is the most prevalent alkoxide of silicon. TEOS is a tetrahedral molecule.
The following molar volumes and densities for the majority of the gaseous elements were calculated from the van der Waals equation of state, using the quoted values of the van der Waals constants. The source for the van der Waals constants and for the literature densities was: R. C. Weast (Ed.), Handbook of Chemistry and Physics (53rd Edn ...
The standard Gibbs free energy of formation (G f °) of a compound is the change of Gibbs free energy that accompanies the formation of 1 mole of a substance in its standard state from its constituent elements in their standard states (the most stable form of the element at 1 bar of pressure and the specified temperature, usually 298.15 K or 25 °C).
Sodium metasilicate is the chemical substance with formula Na 2 SiO 3, which is the main component of commercial sodium silicate solutions. It is an ionic compound consisting of sodium cations Na + and the polymeric metasilicate anions [– SiO 2− 3 –] n.
Here, the silicic acid H 4 SiO 4, or Si(OH) 4, which is equivalent to SiO 2 · 2 H 2 O represents hydrous or amorphous silica for the sake of simplicity in aqueous chemistry. Indeed, the term silicic acid has traditionally been used as a synonym for silica, SiO 2. Strictly speaking, silica is the anhydride of orthosilicic acid, Si(OH) 4.
The magnesium silicide reacts with the acid to produce silane gas, which burns on contact with air and produces tiny explosions. [11] This may be classified as a heterogeneous [ clarification needed ] acid–base chemical reaction, since the isolated Si 4− ion in the Mg 2 Si antifluorite structure can serve as a Brønsted–Lowry base capable ...