voltaxic rift bow

http://pathofexile.gamepedia.com/Voltaxic_Rift
100% of lighnint damage converted to chaos.

did there is any mobs thats reflect chaos?
if not, then voltaxic rift + lighning arrow = OP?

if i take static shocks node which adds : 10% chance to shock. will it work with chaos dmg?

if i apply viper strike stacks an then switch to bow. will viper strike can shock?

Currently (and likely forever) no monsters reflect chaos damage.

Do note that if you use Voltaxic Rift and Lightning Arrow, less damage is converted into lightning damage, so you may not benefit as much from physical damage increases.

But yes, VR is considered to be a fairly strong end game weapon, which is why it sold for 50+ exalts when it was first released.

Not sure how much it's going for now. Check poe.xyz.is if you're curious (or let me in a second) EDIT: On Standard league, there's one 6-linked VR with a 55 exalt buyout price, and another 6-linked VR that someone specifies is 100 pure exalt required with no negotiation. poe.xyz.is also claims there's someone selling a 2-socket VR for 15 exalts, but I can't find it in his shop. The only Hardcore league buyout-listed VR on poe.xyz.is is listed as 50 exalts.

As for your other two questions:

Yes
and
No

If I remember correctly from when VR was released, shock chance nodes (or shock chance anything actually) basically just increase shock chance on damage types that can shock, which before VR was only Lightning Damage (but now includes Chaos because of VR)

Also, it's impossible for Voltaxic Rift to affect a Viper Strike, because shocks can only apply on hit, and when you're hitting with the viper strike weapon, you're not using Voltaxic Rift (the viper strike charges are not hitting, they are a degen debuff. Degen debuffs cannot hit)