COLLECTION

Quali+a+ive Analysis E~mon's NOTE: The papers following Professor Krohn's article on "What Ifas Happened

to Qualtitstive Annalysiq" have been collected over s period of months. Similar collections have appeared in previous August issues [J. C ~ E M . EDUC., 35, 401 (1958); 36, 379 (1959); 37, 407 (1960); 38, 406 (1961); 39, 395 (1962); 40, 413 (1963); 41, 435 (1964); and 42, 436 (1965)l. I t is the Editor's hope that putting the articles together in one issue will prove more xttraet,ive to readers than the more frequently used editorial procedure of scattering items such as these bhrough the pages of several issues. We apologize to authors who thus have had to wait to see their work in print.

We oommend to readen' attention the fact that often these represent the solut,ion of problems given to freshman students in qualitative analysis conrses. We hope that publication in these pages e m stimulate just such activity. If readers merely incorporate these ideas into their own l~boratory instructions, om battle is only half won. If, beyond that, these idem suggest to the readers that they use their own ingenuity in similar fashion, we are gratified.

( What Has Happened . .

Alberiine Krohn University of Toledo

Toledo, Ohio I to Qualitative Analysis? 1 A 7966

1s "aual" dead? On the contrary. qualitative analysis is showing considerable vitality! Three years ago, Hovey reported on a survey made to determine to what extent new concepts in the teaching of chemistry had affected the content and p'ace in the curriculum of courses in qualitative analysis (1). One of the questions askcd was, "What changes are planncd in your treatment of qualitative analysis in the next three years?" This communication rcports a follow-up survey to determine whether the planned changes had been made and what changes are anticipated for the next five years.

Questionnaires were sent to the 458 chemistry depart- ments wh ch had replied to the previous survey. Ad- ditional questionnaires werc sent to recent users of the Brief Qualitative Analysis Examination, to departments newly accredited by the ACS, and to some new Com- munity and Junior Colleges, making a total of 500. Completed questionnaires wore returned by 403 (81%) of the 500.

Table 1 shows the place of qualitat've analysis in the present program. The trend predicted by the 1963 survey is continuing with an approximate 10% increase in courses including qualitative analysis as a part of general chemistry and a corresponding 10% decrease in the number of separate courses. Few replies indicated that no qualitative analysis was taught, but in about 9% of the institutions, less than six weeks of the general chemistry course was devoted to this subject.

Apparent y the separate course continues to bc a favored target in streamlining the crowded under- graduate curriculum. However, the ACS Committee on Professional Training states in their minimum re- quirements under "inorganic chemistry": "Earlier training in descriptive and synthetic inorganic chemis-

survey

Table 1. Place of Qualitative Analysis in Chemistry Proarom

-1963- - 1 9 6 b No. % No. %

Totd number giving qua1 as: Part of general 324 fi3.O 305 73.8 Separate oaune 156 28.7 76 18.4 Part of analytical 45 11.3 32 7 .8

Total number of courses cav- ered by survey 543 . . . 413 . . .

Totd number of students reoresented 110.000 . . . 130.500 . . .

~on;binations of courses: Part of general only 252 55.0 267 65.9 Separate course only 90 19.7 43 10.6 Part of analytical only 16 3 .5 12 3 . 0 Both art of eenerd and a.

Partof general and part of mdlyticd 24 5 .2 11

Separate coune and part of analytical 3 0 .7 6

All three 2 0 . 4 3 Less than six weeks qua1 or no nual 7 1 .5 39

try and methods of separation of ions in aqueous solu- tions is presupposed" (Z). No specification is made as to the manner by which this "presupposed" training is to be obtained. Proponents of the separate course in qualitative analysis believe that it provides a re- markably appropriate setting for the presentation of chemical principles (5). They have objected to "tuck- ing it away" in some corner of the chemistry curriculum such as the second half of the laboratory of the second semester of the general chemistry course (4).

Others have found that qualitative analysis can be correlated effectively with the second semcster of gencral chemistry (5). Many join Swift and Schaeffer

Volume 43, Number 8, Augusf 1966 / 41 9

(6) in their belief that "no more effective method has been found for teaching elementary inorganic chemistry than a coordinated lecture-laboratory course based upon a system of qualitative analysis." They point out that a student must assimilate a formidable mass of information in first year college chemistry and will re- sent the process or forget many of the facts unless the material is related and classified. They further believe "that the periodic table and a system of qualitative analysis are the two most effective aids for this purpose, and that the effectiveness of each is enhanced by the extent to which there is a correlation between them." However, we are warned not to cover too much material in too short a time, because the misuse of qualitative systems in this way has, in the past, led teachers to donbt the intrinsic pedagogical worth of such courses (7).

While no one pretends that the main objective of qualitative analysis is to train analytical chemists, does it have little relevance to modern chemical practice? Consulting analytical laboratories report a real need for qualitative analysis (8). It also seems a bit incon- gruous for a person with a degree in chemistry to be unable to identify quickly, and without the use of a $10,000 gadget, the contents of a container with the label missing. This easily could be the case with the modern generation of chemists whose courses from high school up have shunned "descriptive" chemistry. As Frank put it, "The age of instrumental analysis and of the technician's report tends to glorify costly equip- ment and to overlook the value of simple experimenta- tion, keen observation, and unbiased interpretation. A course which purposely reverses this trend can have a wholesome effect upon the beginning chemist, engineer, or physician" (9).

The laboratory portion of qualitative analysis can be used to develop a spirit of experimental inquiry and critical evaluation which can be the germ of creative research (6). It can help an alert instructor recognize the student who is intellectually and emotionally suited for research so that such students may receive early encouragement in that direction. Frequently in courses which must serve large numbers of unselected freshman chemistry students, qualitative analysis provides the closest practical approach to introductory research on a mass scale (10).

I t was found that schools with large numbers of students usually include qualitative analysis with gen- eral chemistry. Separate courses in qualitative analy- sis rarely had large enrollments. This is partly because they were given more frequently in the smaller institutions and partly because they were offered as special courses for chemistry majors or selected stu- dents in larger institutions.

The only significant change in the average number of semester hours devoted to thestudy of qualitativeanaly- sis is a slight decrease in the number of laboratory hours as shown in Table 2. Thls was predicted by the 1963 survey. Some mentioned that this represents the num- ber of laboratory hours scheduled, but that additional time is available for students who needed it. Several persons pointed out that additional classroom time in general chemistry is spent on subjects related to the theory of qualitative analysis, such as ionic equilibria, solubility product, electrolytic solutions, etc.

Table 2. Average Semester Hours Devoted to Qualitative Analysis

Classroom work: Qua1 in General 18 18 Classroom work: Seosrete Course 31 31 Laboratory work: Q U ~ I in General 46 42 Laboratory work: Separate Course 66 66

Changes planned for the next five years were re- quested in the 1966 survey. The results are shown in Table 3. The only marked trends would seem to be further decrease in the amount of laboratory time and a continued tendency to eliminate separate courses in qualitative analysis. Otherwise, the situation seems to be a bit more stable than it was three years ago.

Table 3. Changes Planned in Treatment of Qualitative Analysis

-Qua1 in general- -Separate eaurs- -1983- -1966 -1963- -1966 No. % NO. % NO. % No. %

Noohangea planned 199 59.4 187 61.4 75 48.7 42 55.3 Inoreaae olaaa time 26 19.1 35 11.5 14 17.7 6 7.9 Deorehseclhsstime 16 11.7 27 8.8 9 11.3 4 5.3 Increase lab time 25 18.3 14 4.6 3 3.7 1 1.3 Decrease lab time 36 28.4 87 22.4 18 20.2 6 7.9 Drop from program :i 2.2 8 2.6 21 26.5 17 22.4 Add to oroaram 5 3.6 R 2.0 0 0.0 0 0.0

Conclusions

Qualitative analysis as a part of general chemistry is gaining in popularity although 18.4'% of the institu- tions surveyed give a separate course following general chemistry. Over half of these plan to continue the practice for the next five years. Some opposition to qualitative analysis was voiced, but the majority of experienced teachers feel that a modem, flexible, well- taught treatment of the subject is of considerable value both to chemistry majors and to those majoring in related fields.

Acknowledgment

The author wishes to express thanks to Dr. Theodore A. Ashford and thc Examinations Committee for finan- cial support of the survey, Dr. Nelson W. Hovey for information based on his experiences with the 1963 survey, and Mrs. Viola Polson for many unpaid hours of assistance.

Literature Cited

(1) HOVEY, N. W., J. CHEM. EDUC., 40,410 (1963). (2) ACS COMMITTEE ON PROFESSIONAL TRA~NING, "Minimum

Standards Used as Criteria in Evalnat,ing Undergraduate Professional Education in Chemistry," 1965, p. 5.

(3) &NO, EDWARD J., "Q~~&litative Analysis and Electrolytic Solutions," Harcourt, Brace & World, Inc., New York, 1959, p. vii.

(4) FREISER, H., J. CHEM. EDUC., 34, 387 (1957). (51 HOVEY. NELSON W.. AND KROHN. ALBERTINE. "Qualitative . . , -

Analysis," Sernoll, Inc., Iowa. City, 1966, p. i. (6) SWIFT, ERNEST H., AND SCHAEFFER, WILLIAM P., "Qnalita-

tive Elemental Amlysis," W. 11. Freeman and Co., San Francisco, 1962, pp. v-ix.

(7) SWIFT, ERNEST H., AND SCHAEFFER, WILLIAM P., "Teachers Manusl for Qualitative Elemental Analysis," W. H. Freeman and Co., Ssn Francisco, 1961, p. 3.

(8) STRONG, F. C., 111, J. CHEM. EDUC., 34, 400 (1957). (9) FRANK, R. E., J. CHEM. EDUC., 34, 383 (1957).

(10) PACKER, J. E., J. CHEM. EDUC., 43,197 (1966).

420 / Journal o f Chemical Education