======================================================================== | Temperatures A +---------+-----+-----+-----+------+--------+------- | 0-2° | 10° | 20° | 30° | 50° | 75° |98-100° --------------------+---------+-----+-----+-----+------+--------+------- Half saturated |Negative |Faint|Fair |Fair |Good |Good |Faint at 20° C | | | | | | | flash One-sixth saturated |Very |Fair |Good |Good |Bright|Very |Good at 20° C | faint | | | | | bright| flash --------------------+---------+-----+-----+-----+------+--------+------- TABLE 13 _Substances Giving Light with Pyrogallol and Hydrogen Peroxide_ Key to column headings: A = Equal volume added to mixture of 1 part M/100 pyrogallol or 1 part 3 per cent H_{2}O_{2} + 1 part M/100 pyrogallol; hence, concentrations final mixture are one-half that given B = Light with pyrogallol C = Light with pyrogallol + H_{2}O_{2} D = Blueing of gum guaiac E = Blueing of gum guaiac + H_{2}O_{2} F = Liberation of oxygen from H_{2}O_{2} ============================================================================= A | B | C | D | E | F ---------------------------------------------+------+------+-----+-----+----- 1 Potassium ferrocyanide | - |Bright| + | | + (K_{4}Fe(CN)_{6} M/10-M/20) | | | | | 2 Potassium ferricyanide | - |Very | - | - |Very (K_{3}Fe(CN)_{6} M/10-M/1,250) | | faint| | | slow | | to - | | | 3 Potassium chromate | - |Good | + | | + (K_{2}CrO_{4} M/20-M/100) | | | | | 4 Potassium bichromate | - |Good | + | | + (K_{2}Cr_{2}O_{7} M/50-M/100) | | | | | 5 Potassium permanganate | - |Bright| + | - | + (KMnO_{4} M/50-M/200) | | | | | 6 Potassium hydroxide | - | - | - | - |Very (KOH M-M/6,250) | | | | | slow 7 Potassium chlorate | - | - | - | - | - (KClO_{3} M/10) | | | | | 8 Potassium persulfate | - | - | - | - | - (K_{2}S_{2}O_{8} M/10-M/128) | | | | | 9 Potassium chromium alum | - |Faint |Very |Very | - (Cr_{2}(SO_{4})_{3}.K_{2}SO_{4} M/10) | | | slow| slow| 10 Ferric ammonium alum | - |Faint | + | |Very