<prompt> Laughing gas is -N2OLewisiteH2SCO2  <response>: Ans. is a i.e., N2OSpecial gaseso Sewer gas - H2S with CO2 and methane.o Marsh gas - Methaneo War gases :Tear gas - i Bromobenzylcyanide BBC, ii Chloroacetophenone CAPBlister gas - Mustard gas and BAL Lewisite gasSickening gas - Diphinyl-amine-chlor-arsineLaughing gas - N2O 