14, Silicium (Si)
lat. silex = Kieselstein |
Säure-Base-Verhalten:
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Säure/Base-Verhalten der Silicium-Oxide: |
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Reaktionen mit: |
HF 100% |
H2SO4 conc. |
HCl 20% |
CH3COOH 25% |
H2O |
NH3 25% |
NaOH 10% kalt |
NaOH 50% heiß |
NaOH liq. 400°C |
SiO2 |
SiF4↑ |
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Na2SiO3 |
Na2SiO3 |
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Legende: |
Lösung |
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Unlöslich |
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sauer → neutral → alkalisch |
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pKS-Werte von Säure-Base-Paaren (HA + H2O ↔ H3O+ + A-) : |
Säurename |
Formel |
pKS-Wert |
Basenname |
Formel |
pKB-Wert |
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Silan |
SiH4 |
35 |
Trihydrogensilicid-Ion |
SiH3- |
-21 |
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Metakieselsäure |
H2SiO3 |
9.51 |
Hydrogenmetasilicat-Ion |
HSiO3- |
4.49 |
Hydrogenmetasilicat-Ion |
HSiO3- |
11.77 |
Metasilicat-Ion |
SiO32- |
2.23 |
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Orthokieselsäure |
H4SiO4 |
9.66 |
Trihydrogenorthosilicat-Ion |
H3SiO4- |
4.34 |
Trihydrogenorthosilicat-Ion |
H3SiO4- |
11.77 |
Dihydrogenorthosilicat-Ion |
H2SiO42- |
2.23 |
Dihydrogenorthosilicat-Ion |
H2SiO42- |
13 |
Hydrogenorthosilicat-Ion |
HSiO43- |
1 |
Hydrogenorthosilicat-Ion |
HSiO43- |
14 |
Orthosilicat-Ion |
SiO44- |
0 |
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Hexaflurokieselsäure |
H2SiF6 |
-3 |
Hydrogenhexafluorosilicat-Ion |
HSiF6- |
17 |
Hydrogenhexafluorosilicat-Ion |
HSiF6- |
1.92 |
Hexafluorosilicat-Ion |
SiF62- |
12.08 |
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