Yes: flux core solder is. No: acid core solder is not.
Solder will conduct electricity, so is not an insulator.
A Conductor, SOLDER IS NOT AN INSULATOR. The most common types of solder are made of tin and lead. Another type is silver solder. All of the materials used are metals and are good conductors of both heat and electricity. If you solder something you would notice if you ever held a wire (without protection) while applying solder to it your finger would probably receive a burn (speaking from experience).
Solder has a relatively low melting point, and it wets many different metals allowing it to be used to join (solder) them together. It is also fairly resistant to corrosion when the correct solder alloy is applied to the work. We see a lot of solder used in electrical and electrical applications, so it's a fairly good electrical conductor.
True
If it is a broken conductor connection, you can solder the connections. Someone please add some more, this is not a complete answer.
with solder
Yes, usually no problem. If you know how to solder, then solder away.
In some solder it is. But even if it is in the solder you should still use flux.
Solder is a metallic alloy
solder is use for to make jewles
Depends on the kind of solder.