What is the name of this song in ep1 Hibike Euphonium 2 Between 24:00 to 26:00, can someone telling me what is the song name? 

Hibike! Euphonium 2 Episode 1
The song is Polovtsian Dances from the opera Prince Igor by Alexander Borodin.

Funny that the first Youtube video that hits on Google seems to also have attracted other fans of the anime as well.