Hum, snake-style chain. It must be the very final, soldered-on link that you wish to open, Joanne. Am I correct? In a situation such as this, why open it at all? Reclosing it would make a major weak point in whatever you are making, because it would be hard to match the original factory closure.
Why not just add to this link by using a piece of wire to make a wrapped loop (be sure to include the chain link in the loop before wrapping it closed), and then connecting it to your jump ring or wire, and then make another wrapped loop at the opposite end. Or you could attach the chain to jump ring or wire by adding a larger wrapped loop, and then add things to the larger loop. At Wire-Sculpture, we encourage "traditional" wire designs, using no solder or glue. By adding components to your chain with wrapped loops, you'll avoid possible weak points (such as a simply closed jump ring) and create a durable piece of jewelry.
Answer contributed by Dale "Cougar" Armstrong