Question: what is the k in the rate law equation
[{'answer': 'reaction rate constant', 'provenance': [{'wikipedia_id': '1677334', 'title': 'Rate equation', 'start_paragraph_id': 2, 'start_character': 359, 'end_paragraph_id': 2, 'end_character': 381, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'answer': 'rate coefficient of the reaction', 'provenance': [{'wikipedia_id': '1677334', 'title': 'Rate equation', 'start_paragraph_id': 2, 'start_character': 386, 'end_paragraph_id': 2, 'end_character': 419, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '1677334', 'title': 'Rate equation', 'start_paragraph_id': 2, 'start_character': 0, 'end_paragraph_id': 2, 'end_character': 543, 'bleu_score': 0.904300433468425, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 9019097537518195175}, 'section': 'Section::::Abstract.'}]}]