Relative strength of metal hydrides as reducing agents

Question:
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Out of $CH\_4, CaH\_2, FeCl\_2$ and $BeH\_2$, which compound would produce the most strongly reducing aqueous solution?


Thoughts:
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Out of the hydrides, I would say that $CaH\_2$ stands a good chance at being the strongest reducing agent, since the Ca-H bond energy is lowest (allowing the extremely reducing hydride to be released more readily into solution). The only rationale I can think up for this is the relative sizes of the other ion in the hydrides (Ca>Be>C) which implies that bond length is greatest in the calcium hydride (thus bond energy is lower). I am unsure as to how I should tackle the chloride compound. Much assistance is needed.


