What is the name of the section in Sonata Allegro form that develops motives based on Themes 1 and 2?

The section in Sonata Allegro form that develops motives based on Themes 1 and 2 is known as the Development. During the Development, composers take the thematic material introduced in the Exposition and manipulate it through various means, such as altering the harmony, changing the key, or employing contrapuntal techniques. This creates a sense of tension and exploration, allowing the composer to explore different emotional landscapes and ideas.

In contrast, the Exposition presents the main themes for the first time, while the Recapitulation restates these themes in the home key, providing resolution. The Coda serves as a concluding section that wraps up the musical ideas presented throughout the movement. The Development is crucial for providing depth and contrast, showcasing the composer's creativity in transforming the initial themes.