Bankruptcy & Lien on home
If a person is sued by a bank for an amount owing on an unsecured line of credit and the bank then places a lien on the person’s home, will declaring bankruptcy remove the lien or will the bank still be able to take the house?

A lien is just like a mortgage; it is not automatically removed in a bankruptcy. Once a lien is in place, it will only be removed if you repay the debt, or if the house is sold, or if the bank for some reason agrees to remove the lien.
It may be possible to have a lien removed as a condition of a proposal, but this is a complicated area and a consultation with a trustee would be necessary.