[{"from": "human", "value": "Describe this molecule. [O][As][=Branch1][C][=O][Branch1][C][O][O-1]"}, {"from": "gpt", "value": "The molecule is an arsenate ion resulting from the removal of one proton from arsenic acid. It is a conjugate base of an arsenic acid. It is a conjugate acid of an arsenate(2-)."}]