One aspect of the present invention relates to ionic liquids comprising an anionic sweetener. Another aspect of the present invention relates to the use of an ionic liquid of the present invention comprising a pendant Bronsted-acidic group to catalyze a Bronsted-acid-catalyzed chemical reaction. A third aspect of the present invention relates to ionic liquids of the present invention comprising a pendant nucleophilic group, e.g., an amine. Still another aspect of the present invention relates to the use of an ionic liquid of the present invention comprising a pendant nucleophilic group to catalyze a nucleophile-assisted chemical reaction. A fifth aspect of the present invention relates to the use of an ionic liquid of the present invention comprising a pendant nucleophilic group to remove a gaseous impurity, e.g., carbon dioxide, from a gas, e.g., sour natural gas. A sixth aspect of the present invention relates to heat storage media comprising an ionic liquid of the present invention.