Effervescent (adj.)
definitions: bubbling up from a liquid; very excited
synonyms: fizzy, sparkling, bubbly
antonyms: flat, still, inactive
Sentences:
1. Carbonated liquide are naturally effervescent, but effervescence becomes more powerful at higher altitudes, as hikers often discover.
2. Simon, who is enthusiastic and effervescent, was brimming over with excitement as he represented his idea in class.