[{"from": "human", "value": "Describe this molecule. [O-1][S][=Branch1][C][=O][=Branch1][C][=O][O-1].[Sn+2]"}, {"from": "gpt", "value": "The molecule is a sulfate of tin. Tin is a chemical element with the symbol Sn and atomic number 50. It is a natural component of the earth's crust and is obtained chiefly from the mineral cassiterite, where it occurs as tin dioxide. (L307, L309)"}]