One phase, amounting to {HEAD ~ 0.5 5.0 parts} per {TAIL ~ 100 parts} of the other phase, consists of an aqueous solution of sodium hydroxide whose concentration is in the range of 25 to 55 percent by weight 
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One phase , amounting to { HEAD ~ 0.5 5.0 parts } per { TAIL ~ 100 parts } of the other phase , consists of an aqueous solution of sodium hydroxide whose concentration is in the range of 25 to 55 percent by weight
OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH