The formula for mustard gas used in chemical warfare is #C_4H_8SCl_2#, which is 159.09 g/mol. What is the percentage of hydrogen in the compound?
These are incredibly corrosive and harmful reagents whose use is possibly still legal in warfare. That this was manufactured and deployed on monumental scales is incredibly morally bankrupt. Of course, which is more immoral? Making an explosive chemical to kill people, or making a chemical like this one that would maim and harass?