- 7 
Another color imetric method for the identification and determination 
of chlordane specifies that 1 ml. of a 0,1 - 1.0 percent solution of 
chlordane in ethanol "be mixed with 1 ml. N potassium hydroxide in ethanol 
and 1 ml. of a reagent prepared "by dissolving 0.1 gram of p-aminophenol 
in 100 ml. of 80 percent ethanol. When heated to 100° C. for 5 to 10 
minutes, the appearance of a "blue color indicates the presence of 1 mg. 
or more of chlordane. None of the other common insecticides interferes. — 
Palumho Q5ll. 
In the laboratories of the Division of Insecticide Investigations, 
Bureau of Entomology and Plant Quarantine, the total chlorine in chlordane 
is determined by decomposing the sample with sodium in refluxing anhydrous 
isopropyl alcohol and titrating the sodium chloride formed with N/10 
silver nitrate solution, using an electrometric titrimeter. Chlordane is 
calculated hy multiplying the total organic chlorine content "by 1.44, a 
factor "based on the fact that pure chlordane contains 69.22 percent of 
chlorine. 
Eomano ( 3 , 98 ) has pointed out that temperature, concentration of 
chlordane in solvent, and ratio of potassium hydroxide to solvent influ- 
ence the dehydrohalogenation of chlordane and that a carefully standard- 
ized method is necessary in order to obtain reproducible results. 
Eomano refluxes a solution of a 0.5 gram of chlordane in 20 ml. of 
petroleum ether with 20 ml. of N alcoholic potassium hydroxide at 80° C. 
for 30 minutes and determines the chloride ~oy Volhard' s method; 1 ml. 
0.1 N silver nitrate = ^7»6 mg. chlordane. This factor used "by Eomano 
is an arbitrary one. The loss of one chlorine atom from the molecule 
of chlordane, C^oH^Clg, calls for the value 1 ml. 0.1 N silver nitrate = 
kO.Q mg. chlordane. 
Davidow (98) in 1950 described a spectropho tome trie method for the 
quantitative estimation of technical chlordane which is also applicable 
to the estimation of alpha-chlordane, beta-chlordane, heptachlor, and 
trichloro 237 (all present in technical chlordane) when only one is 
present. The procedure is to develop a colored reaction product "by 
heating chlordane in n-hexane with diethanolamine-potassium hydroxide 
reagent in a boiling water hath for 30 minutes and note the absorhency 
at 521 millimicrons in a Beckman spectrophotometer. 
Technical chlordane interferes in the method for the determination 
of heptachlor in which equal volumes of the suspect solution and a 0.5 
molar solution of ethanolamine and of potassium hydroxide in butyl 
Cellosolve are mixed and heated in a boiling water bath for 15 minutes, 
the development of a pink to deep violet indicating the presence of 
heptachlor. — Velsicol Corp. (*+79~). 
Chlordane does not interfere in the colorimetric estimation of 
aldrin in which the aldrin is reacted with phenylazide to form a dihydro- 
triazole derivative which yields an intense red color when reacted with 
diazotized dinitroaniline in alcoholic hydrochloric acid. — Danish and 
Lidov (22). 
