I imagine champagne is like many other bubbly beverages. Much like a good beer once chilled it should stay chilled. it the bottle stays chilled I imagine it keeping for ever. Let me warn you though, once it warms up, chilling it again can and will do just like a beer that has been rechilled, it can get skunky.
Yes, but try to limit the amount of times that happens.
Since champagne is chilled, the surface of the liquid once opened chills the air to it's dew point creating what is known as the "Heather" of the champagne. French people from Reims in the Champagne region believe that breathing in this Heather has a rejuvenating effect on health
It depends on the temperature of the heat. Champagne is best served cold, or at least chilled. The glass has been produced to withstand pressure of the champagne within. Adding an external heat source to the bottle is rather going too far!
Sambuca should be chilled.
I think please review the question. Are you asking for champagne or cognac??? Champagne is served chilled whereas cognac is served at room temperature(if drinking neat) or served alongwith warm water. Actually, I believe s/he is asking about fine champagne, which is a type of cognac. You can drink fine champagne either at room temperature or chilled - I personally would recommend chilled.
3 or 2 days
NOPE
It is a 375ml bottle of champagne (half the size of a standard bottle).
The label will have the year on it.
6 glasses in a bottle of Champagne
You can observe water droplets on the surface of a chilled bottle because the temperature of the atmosphere is a different temperature to that of the temperature in the chilled bottle.
A split of champagne is a half bottle