which of these molecules are ketones? check all that apply. a a three carbon chain. all carbons are bonded to h atoms. b a three carbon chain. one outer carbon is bonded to an o h group. c a three carbon chain. the middle carbon is double bonded to an o atom. d a three carbon chain. one outer carbon is double bonded to an o atom and single bonded to an h atom. e a three carbon chain. one outer carbon is double bonded to an o atom and single bonded to an o h group. f molecule h 3 c o c h 3.