Red giants and angular momentum question

[ko_kyi]

I was watching a Discovery channel program about the future of our Sun (and any similar star). They were describing the expansion of the star as it goes to Red Giant stage, and how it would eventually expand to include Mercury. At first I thought that the molten planet would slow due to friction within the perimeter of the star and spiral down into the core, but then it occurred to me that the expanded star would still retain the angular momentum, and the gas molecules might be orbiting the center of gravity at the same speed, so the blob of ex-Mercury would just continue as it evaporated away. Correct? Incorrect?

Just one of the weird things I ponder. I'd love to hear some evaluations of what would happen. Thanks in advance.

 

[Borek]

5000K (red giant surface) is enough to evaporate everything. My guess is that planets will evaporate and diffuse. Angular momentum will be there, just as a part of total angular momentum of the star.