Is it possible to change between two fontawesome icons on hover?

Question

I have an anchor tag with a font-awesome icon as follows

Answer 1

Simple way open css file of font awesome and change icon code on hover...

for example below is the code for lock icon

content: "\f023";

and here below is the code for unlock icon in css which you can put under :hover

.icon-unlock:before {
  content: "\f09c";
}