The phrase "I snapped on the Spanish part" can be interpreted in a couple of ways, depending on the context. Generally, "snapped" can mean to suddenly become angry or to respond sharply to something. However, if you're referring to completing a task or performing well, it could mean that you excelled or did exceptionally well on the Spanish portion of something, like a test or presentation.
If you're using "snapped" to indicate a sudden burst of