P helmets dipped in hexamine were used by Allied troops against these types of weapons.
An inventor of these types of weapons learned his wife Clara Immerwahr had killed herself after he returned from watching their first use. Hugo Stolzenberg supplied weapons of this type for use in Spain's conflict with Abd el-Krim during the Third Rif War. In the 1930s, the company IG Farben developed a new weapon of this type codenamed GA. One weapon of this type was developed at the (*)  Kaiser Wilhelm Institute under the direction of Fritz Haber and was first used on April 22, 1915, at Ypres  (EEP-ruh) . P helmets dipped in hexamine were used by Allied troops against these types of weapons. Some of these types of weapons make use of blister agents and were dispersed through the wind. For 10 points, name this type of weapon that might choke soldiers in trenches not wearing masks.
An inventor of these types of weapons learned his wife Clara Immerwahr had killed herself after he returned from watching their first use.
chemical  weapons [or mustard  gas ; or  chlorine  gas; or poison  gas ; or  phosgene  gas]