Section 21.101 - tert -Butyl alcohol(a)Acidity (as acetic acid). 0.003 percent by weight maximum.(c)Distillation range. When 100 ml of tertiary butyl alcohol are distilled, none should distill below 78 °C. and none above 85 °C. More than 95 percent should distill between 81 °-83 °C.(d)Dryness at 20 °C. Miscible without turbidity with 19 volumes of 60° Be1. gasoline.(e)Freezing point (first needle). Above 20 °C.(f)Identification test. Place five drops of a solution containing approximately 0.1 percent tertiary butyl alcohol in ethyl alcohol in a test tube. Add 2 ml of Denige's reagent (dissolve 5 grams of red mercuric oxide in 20 ml of concentrated sulfuric acid; add this solution to 80 ml of distilled water, and filter when cool). Heat the mixture just to the boiling point and remove from the flame. A yellow precipitate forms within a few seconds.(g)Nonvolatile matter. Less than 0.005 percent by weight.(h)Odor. Characteristic odor.(i)Residual odor after evaporation. None.(j)Specific gravity at 25 °/25 °C. 0.780 to 0.786.T.D. ATF-133, 48 FR 24673, 6/2/1983. Redesignated by T.D. ATF-442, 66 FR 12854, 3/1/2001