$$\ce{6HF +SiO2->H2SiF6 +2H2O}$$

$\ce{HF}$ reacts with $\ce{SiO2}$ to form $\ce{H2SiF6}$.

Do other hydrogen halides like $\ce{HCl}$ and $\ce{HBr}$ react with group 14 oxides in the same way?

  • $\begingroup$ Are you sure it's even useful to ask for the reactivities for all of group 14? The reactivities of lead and carbon are extremely different. $\endgroup$ – ringo Oct 14 '16 at 15:01
  • $\begingroup$ @ringo But still there must be some sort of periodic trend. $\endgroup$ – Resorcinol Feb 2 '17 at 14:51

All reactions taken from this site.

First some maths: 4 hydrogen halides can react with 5 Group 14 monoxides and dioxides. So, there should be 40 different chemical reaction combination possible. But not all reactions are feasible.


  1. With $\ce{SiO2}$ (already mentioned)

  2. $$\ce{GeO2 + 4HF → GeF4 + 2H2O}$$

  3. $$\ce{SnO + 2HF ->[333 K] SnF2 + H2O}$$


  1. $$\ce{GeO2 + 4HCl(g) ->[450-500 C] GeCl4 + 2H2O}$$

$$\ce{GeO2 + 4HCl(l) ->[170-180 C] GeCl4 + 2H2O}$$

  1. $$\ce{SnO + 3HCl → H[SnCl3] + H2O}$$
  2. $$\ce{SnO2 + 6HCl → H2[SnCl6] + 2H2O}$$
  3. $$\ce{PbO + 2HCl → PbCl2 + H2O}$$
  4. $$\ce{PbO2 + 4HCl → PbCl2 + Cl2 + 2H2O}$$

$\ce{HBr}$ and $\ce{HI}$ do not show such type of reaction.


Other posters have already commented on the thermodynamics of the reaction, but I will just point on the fluoride has a very high affinity for silicon, more so that oxygen. This is driving the thermodynamics of your reaction.

Fluoride is commonly used to remove silicon-based protecting groups for alcohols because it will displace the oxygen when other halides will not.


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