[{"from": "human", "value": "Use the given information to create a molecule that fulfills the desired purpose. The molecule is the potassium salt of formic acid. It has a role as a buffer. It is a potassium salt and a one-carbon compound. It is functionally related to a formic acid."}, {"from": "gpt", "value": "[C][=Branch1][C][=O][O-1].[K+1]"}]