A DEVICE FOR PRODUCING FLAME SPECTRA ARTHUR R. CLARK College,
Pennsylvania State College, State
SINCE the test-tube method for flame testing produced several new flame tests for the common and
1
I
I1
Pennsylvania
elements, and similar work on the rarer elements by this method, reference may be made to two papers of the The figure gives a close-up of the arrangement used for producing a spectrum by this method. The one end of the spectroscope may be observed to the extreme left. The Bunsen burner is placed at an angle so that any excess liquid will not disturb the flame. A twoto three-inch flame is used and a micro-buret is used to supply the liquid. The buret contains the solution to be analyzed and the stopcock adjusted so that a drop is liberated just as the preceding drop is dried upon the test-tube. thereby producing a continuous flame. After the arranpement is vlaced in workine condition, only one individual is neeied to do the spectrum work which is a great advantage in many respects, when compared with the use of the platin--wire method in s~ectrumanalvsis. analvsis. , .in oualitative . , . and spectrum experiments in the elementary physics course. A Hilger wave-length spectroscope was used in this work. The elements that produced flames by this method and did not produce any visible spectrum lines were tin, antimony, selenium, germanium, titanium, tellurium, nickel, aluminum, and bismuth. Strontium produced ali of its ordinary lines, as did barium, calcium, sodium, potassium, lithium, thallium, indium, caesium, and rubidium. Lead, manganese, and copper produced rather broad bands; however, these are the only three heavy metals that produced spectra by this method, thereby makinp readines - wectrum . much easier for mixtures.
-
-
rarer elements, i t was of much interest to find what observations could be made by this method by using a spectroscope. For the work done on the common
CLARK,A. R.,"The test-tube method for flame testing," 1
test applied to the rarer e~ements,~~ ibid., 13, 383-4 (1936).
