For 10 points—name this opera about Leonore by Ludwig van Beethoven.
In one scene in this work, a group sings the song "O welche Lust" before remembering that they need to stay quiet or they could be caught, and that group would later sing "Leb wohl, du warmes Sonnenlicht" when they are discovered roaming free in the garden by a character who sings "Ha, welch ein Augenblick!" before telling another character to sound a trumpet when a minister arrives.  In addition to Pizarro, one scene in this work sees Marzelline sing "Jetzt, Schätzchen, jetzt sind wir allein", in which she reveals that she is in love with the title character, who reveals himself at the end of this work to be the wife of Florestan.  For 10 points—name this opera about Leonore by Ludwig van Beethoven.
In one scene in this work, a group sings the song "O welche Lust" before remembering that they need to stay quiet or they could be caught, and that group would later sing "Leb wohl, du warmes
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