Stability of Halide Salts of Different Metals


> 
> Between $\ce{EuCl3}$, $\ce{RuCl2}$, and $\ce{VCl}$, order in
>  increasing stability.
> 
> 
> 


I don't know if this is a dumb question and if the answer is blatantly obvious, but I don't understand how to "solve" this question. Is there a rule that determines the stability of chloride salts / any salt in general that can be applied by just referring to a periodic table?


(My rationale for this problem was that Eu and Ru have 3+ and 2+ charges, respectively, and since Eu's 3+ oxidation state would empty both its s-orbital and d-orbitals and Ru's 2+ state would empty its s-orbitals, the complex would be able to form (Just to show that I've done work) but that honestly seems obviously wrong as well.)


This is not an HW question.


