Subject: What is the connection between Gay-Lussac's Law and my experiment?

In class, we boiled water in a soda can.  When steam was observed coming out 
the top we placed it upside-down into a trough of water.  The can popped 
inward, and there was more water inside than we started with.  I think that the 
escaping gas created a lower pressure inside the can than outside.  Placing the 
can in the water cooled the remaining vapor rapidly.  Since a gas occupies 1000 
times the volume of its respective liquid, less volume was needed in the can.  
Is this theory at all correct?  My teacher suggested Gay-Lussac's Law and the 
word "vacuum", but I'm still stuck.  Can you help me?

Re: What is the connection between Gay-Lussac's Law and my experiment?