APPENDIX 1 
PHYSICAL CONSTANTS OF SOME ORGANOPHOSPHATE COMPOUNDS* 
Kt = ln O Where cy = Initial concentration and 
aid 
C = Concentration at time "t." 
This then reduces to the following for the half-life: 
eo 
50° 
Because of the low solubility of preparations of the "E-605" group, 
the experiments in these cases were conducted in 20% aqueous methanol 
at 70°C. At 40°C some of the substances give precipitates, so that 
the measurements were uncertain. 
COMPOUND Half-Life 70° [HRS. ] 
E-605 (IV) 64 
Methy1-E-605 (XVIII) 13 
Isochlorthion (XX) 9 
Chlorothion (XIX) Ved 
PREP. St 133 CXL) aD 
* (1049) 
479 
