It is appropriate IF you are being professional.
Consider these tips:
1. Know what your objective is before approaching the person (be sure it’s something he/she can say yes to, or a comment that is appropriate and MEMORABLE).
2. Be aware of the body language. If he/she keeps backing up, don’t keep moving forward. GIVE PEOPLE THEIR PERSONAL SPACE!
3. If you ask a question, listen and accept the answer, whether you like it or not. DON’T debate someone in order to meet your agenda.
4. Know when it’s time to say goodbye and walk away.
5. Take note of all of the mistakes the group around you is making. (I just threw this one in so you can meet the person and learn a huge amount about networking in a miniscule amount of time)
If you have a question, put it in the comment section.
To your success!