Dehydration or Decarboxylation of acids by MnO/300°C
(1) This reaction occurs among two molecules of carboxylic acids. Both can be the same or different.
(2) If one of the carboxylic acids is HCOOH after that this acid goes through decarboxylation as this acid is the just only monobasic acid which goes through decarboxylation even in the absence of catalyst.