basically an asp.net application can contain only one
web.config file. so there is no possibility of using 2
web.config files for connection in an application.

Above Answer is not exactly right.we can have more than one 
web.config file in an application. We can have web .config 
file for every folder in application.but not 2 web.cofig in 
one place

You can use multiple web.config in multiple folders in one 
application but not in same folder.You can use conection 
string in same folder's web.config not others if you want 
to use other connection string then you can assign many 
keys for connection string in same web.confg.for that not 
nessacary to use other web.confg.

No