[{"from": "human", "value": "Could you provide a description of this molecule? [C][=Branch1][C][=O][C][=O]"}, {"from": "gpt", "value": "The molecule appears as yellow crystals melting at15 \u00b0C. Hence often encountered as a light yellow liquid with a weak sour odor. Vapor has a green color and burns with a violet flame."}]