Silicic acid with the formula (HO)3–Si–O–Si–(OH)3
Pyrosilicic acid
Names
IUPAC name
Trihydroxysilyl trihydrogen orthosilicate
Other names
disilicic acid
Identifiers
ChEBI
ChemSpider
26937
InChI=1S/H6O7Si2/c1-8(2,3)7-9(4,5)6/h1-6H
Y Key: KDJOAYSYCXTQGG-UHFFFAOYSA-N
Y
Properties
H 6 O 7 Si 2
Molar mass
174.211 g·mol−1
Conjugate base
Pyrosilicate
Except where otherwise noted, data are given for materials in their
standard state (at 25 °C [77 °F], 100 kPa).
Chemical compound
Pyrosilicic acid is the chemical compound with formula H6 Si2 O7 or (HO)3 SiOSi(OH)3 . It is one of the silicic acids and has pyrosilicate as its conjugate base .
It was synthesized, using nonaqueous solutions, in 2017.[ 1]
H
6
Si
2
O
7
(
aq
)
⟶
2
SiO
2
(
s
)
+
3
H
2
O
{\displaystyle {\ce {H6Si2O7(aq) -> 2 SiO2(s) + 3 H2O}}}
Pyrosilicic acid may be present in sea water and other natural waters at very low concentration.[ 2] [ 3] Compounds formally derived from it, such as sodium pyrosilicate , are found in the sorosilicate minerals.
^ Igarashi, Masayasu; Matsumoto, Tomohiro; Yagahashi, Fujio; Yamashita, Hiroshi; Ohhara, Takashi; Hanashima, Takayasu; Nakao, Akiko; Moyosh, Taketo; Sato, Kazuhiko; Shimada, Shigeru (2017). "Non-aqueous selective synthesis of orthosilicic acid and its oligomers" . Nature Communications . 8 (1): 140. Bibcode :2017NatCo...8..140I . doi :10.1038/s41467-017-00168-5 . PMC 5529440 . PMID 28747652 .
^ Katsumi Goto (1956): "Effect of pH on Polymerization of Silicic Acid". Journal of Physical Chemistry , volume 60, issue 7, pages 1007–1008. doi :10.1021/j150541a046
^ M. F. Bechtold (1955): "Polymerization and Properties of Dilute Aqueous Silicic Acid from Cation Exchange". Journal of Physical Chemistry , volume 59, issue 6, pages 532–541. doi :10.1021/j150528a013