Final answer:
By age 13, Wolfgang Amadeus Mozart had composed sonatas, operas, concertos, quartets, and symphonies. These pieces reflect the structural and stylistic conventions of the Classical era, which later influenced Romantic era music.
Step-by-step explanation:
The types of musical pieces Wolfgang Amadeus Mozart had written by age 13 include:
- Sonatas
- Operas
- Concertos
- Quartets
- Symphonies
Each of these forms range in structure, style, and content, evolving from the Classical era traditions. Despite the different characteristics of various musical forms, they often share common elements like notes, chords, and melodic styles.
During Mozart's time, the Classical period focused on clarity, balance, and formality in music composition. Following this, the Romantic era composers built upon classical principles while embracing more expressive and dramatic elements in their works. These periods produced music that is well-regarded and still performed regularly today.