[cassar.zach]

I have this question. Explain why Sn and Pb have stable dichlorides, whereas Si does not (i.e. SiCl2 does not exist).

[billnotgatez]

Forum rules require you show some work so we can get an idea where you need help
please read forum rules

[cassar.zach]

Sorry for that. I didn't know that I needed to show some working before.

Well basically, this is what I compiled.

Sn and Pb have the longest and weakest bonds and thus forming a bond with Cl can be easily done. This is because they can form an active complex when reaction with H2O. On the other hand, SiCl4 cannot form because it loses Cl quickly to form Cl2.

I don't know if this is correct and I cannot get to the roots of what the answer could be.

[spirochete]

Wouldn't a better way to word this be: Why are the larger group 4A elements stable in the 2+ oxidation state, while the smaller ones (silicon and carbon) prefer to exist as +4 if possible?

[antimatter101]

Hello everyone,

Did you know that this topic has been discussed extensively across this forum already? There is no 100% explanation - chemists are still unsure about the exact nature of the culprit. Anyway, the phenomenon is called the inert pair effect, and only affects the heavier members of the groups.