The Konzertstück in F minor for Piano and Orchestra, Op. 79, J. 282, was written by Carl Maria von Weber, and he started work on it in 1815, and completed it on the morning of the premiere of which opera, with spoken dialogue in three acts?
Der Freischütz Der Freischütz , Op. 77, J. 277, (usually translated as "The Marksman" or "The Freeshooter") is a German opera with spoken dialogue in three acts by Carl Maria von Weber with a libretto by Friedrich Kind. It premiered on 18 June 1821 at the Schauspielhaus Berlin. It is considered the first important German Romantic opera, especially in its national identity and stark emotionality.
La finta semplice La finta semplice ("The Fake Innocent"), K. 51 (46a) is an opera buffa in three acts for seven voices and orchestra, composed in 1768 by then 12-year-old Wolfgang Amadeus Mozart. Young Mozart and his father Leopold were spending the year in Vienna, where Leopold was trying to establish his son as an opera composer. He was acting on a suggested request from the Emperor Joseph II that the young boy should write an opera.