An Oldie but Goodie Test for Carbon Dioxide Carbondioxidegasdoes not support combustion and- be testedforwith alighted match. Asaferand more"colorful" test1 uses red (pink) phenolphthalein paper. This is prepared bv.imoremantinefilter Dave= . . . circles with 0.05 M barium hydroxide soluiion, inch I& mL uf xhr'h contains i0 ml. ofO.Ioi.phrnolphtholein sulut~m.Aiter the paper dnc-, thr circles nrr rut into I-cnt wide strips. To use for testing, wet the rrd ip:nk phenolphthalem paper wrth water and plncr i t in thecarbon diuxideatrnusphrrt. The redrp~nk,ealnrisdischarged.Carbun diuxldereactr with watrrmforrn carhonic acid, which decolorizes the red (pink) phenolphthalein. 'The Merck Index, 5th ed., 1940. page 710
Al Hazari University of Mississippi University, MS 38677
778
Journal of Chemical Education
