would this exhibit electromagnetism just like a copper wire solenoid? Could it actually be even more efficient than a copper wire solenoid?
It would be a lot less efficient, as the resistance would be higher than copper. A lot higher. And then you have the problem of electrolysis occurring where the wire connects to the salt water. Silver has a lower resistivity than copper, so it would have a higher efficiency, that is about the only conductor better than copper. .
Only if a current(which would be limited by the resistance of the salt water or copper) was applied.So your question is which has less resistance per unit of cross section.Which would be copper.So the answer is no it wouldn't be more efficient(excess heat).Besides to do so would be a hard task what with leaks,space for the plastic tube etc. since the field is determined by ampere turns.
