The present invention relates to a hydrofluorinating process which comprises reacting a fluoroolefin with hydrogen fluoride in the liquid phase in the presence of a hydrofluorination catalyst in the reaction zone of a reactor, said reactor comprised of a reactor body having a length to diameter ratio of about 2:1 or greater; a stirred reaction zone containing said hydrofluorination catalyst, which may be prepared in situ, at least one inlet for supplying said hydrogen fluoride and fluoroolefin to the reaction zone and at least one outlet for recovering said fluoroalkane, said stirrer disposed in the reaction zone and comprising a plurality of blades fixedly attached to shaft drivable by a motor, said blades extending from about the bottom of the reaction zone to about the top of the reaction zone and said shaft extending on a longitudinal axis from the bottom of the reactor to the top of the reactor, said stirrer being rotated at a speed sufficient to promote a swirling of the liquid to effect the occurrence of hydrofluorination reaction and minimize overfluorination. The present invention also relates to said hydrofluorination reactor.