A Modified Micro-Boiling-Point Technique Many teaching laboratories now stock commercisl melting point capillaries (0.9-1.1 mm od X 90 mm; e.g., Kimax 34505). We have found that a. 5-10-mm length cut from the sealed end of a commercial melbing paint tube serves expediently ass. fine capillary bubbler when inserted, open end downward, into the liquid in the boiler tube (10mrn X 7Smm test tube) of a micro boiling paint apparatus. The lengths of the short capillary csn be varied, depending on the volume af liquid sample, to allow for near complete submersion of the capillary in the liquid and diminat,ion of thermal eradient. Other ex~erimentaldetails are the same as described in the literature.'
reproducible and compared well with those obtained by the standard lab manual technique. 'SHRINER,R. L.,FUSON,R. C., AND CURTIN,D. Y., "The Systematic Identification of Organic Compounds," (5th ed.), John Wiley & Sons, Inc., New York, 1964. ADAMS,R., JOHNSON, J. R.,A N D WILCOX,C. F., JR., "Laboratory Experiments in Organic Chemistry," (5th ed.), The MacMillan Co., New York, 1963, p. 33.
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