user: Question: What is the chemical class for RI?
Columns: ['Chemical class', 'Group', 'Formula', 'Prefix', 'Suffix', 'Example']
Types: ['text', 'text', 'text', 'text', 'text', 'text']
Sample row: ['haloalkane', 'halo', 'RX', 'halo-', 'alkyl halide', 'Chloroethane (Ethyl chloride)']
SQL:

assistant: SELECT "Chemical class" FROM "Table" WHERE "Formula" = 'RI';