How many bubbles are there in a bottle of champagne?

The answer varies from 49 Million to 250 Million bubbles, but 2 scientific methods were related on this page:

http://www.beekmanwine.com/prevtopam.htm

I have copied the text (minus some extraneous verbiage) below:

Two attempts have been made to count/calculate the number of bubbles in a bottle of Champagne. The estimates differ greatly, but both may surprise you.

1. Bill Lembeck, a scientist, was opening a bottle of Champagne when he speculated on how many bubbles would soon come bursting to life. Having realized that there would probably not be the same number of bubbles in every bottle, Bill Lembeck decided that he would be satisfied with a reasonable estimate. He then determined that essentially all he had to do was calculate the volume of CO2 in a 750 ml bottle of Champagne and divide this number by the volume of an average bubble.

Putting aside such questions as whether all the bubbles are the same size, and the impact of temperature on the size of the escaping bubble, Lembeck doggedly attacked the problem in a systematic way. First, he established that the average pressure in a Champagne bottle was about 5.5 atmospheres at 20 degrees C. In other words, he explained, a bottle of Champagne contains 5.5 times its volume in the form of gas produced by the second fermentation in the bottle. Accordingly (at standard atmospheric pressure), a 750 ml bottle contains 4,125 ml (252 cubic inches) of gas dissolved in the wine. The gas is not released until the cork is removed.

The next step in Lembeck's scientific inquiry was to determine the size and volume of an average Champagne bubble. With the aid of a machine called an "optical comparator," Lembeck was able to determine the average bubble diameter at the surface of the wine in a glass. It was 0.5 mm (0.020 in). Knowing this, it was child's play for him to compute the volume of the average bubble; a minuscule 69 millionths of a ml (4.2 millionths of a cubic inch).

A non-scientist would hastily have concluded that all that remained was to divide the total volume of gas by the volume of an average bubble. Lembeck, being a scientist, knew that at least one 750 ml volume of the CO2 dissolved in the liquid would remain behind when the cork was removed: 750 ml of CO2 that would never burst. The available CO2 would therefore be the originally calculated CO2 (4,125 ml) minus the trapped CO2 (750 ml), leaving 3,375 ml (206 cubic inches) destined for "bubbledom". Finally, all that remained for Lembeck to do was divide this available volume of gas by that of the average bubble.

Lembeck obtained the astonishing number of 49 million bubbles per bottle.

2. Bruno Dutertre headed a three year, $7 million joint project between Moet & Chandon and Heineken to "Understand and Study the Influence of Chemical and Physical Parameters on the Formation of Bubbles and the Stability of the Mousse" between 1986 and 1989. At the heart of this research was a camera based "artificial vision" system that was linked to a computer and built by ITMI (Industrie et Technolgie de la Machine), which recorded the release of bubbles and counted them.

According to Monsieur Dutertre, there are on average 250 million bubbles in a bottle of Champagne.

Another estimate is that tghere are 49 million bubbles in a bottle of champagne.