Question: a compound is broken down by chemical means during what process
[{'answer': 'Chemical decomposition', 'provenance': [{'wikipedia_id': '1533184', 'title': 'Chemical decomposition', 'start_paragraph_id': 0, 'start_character': 0, 'end_paragraph_id': 0, 'end_character': 22, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}]