The PROBLEM CONTENT of TWELVE HIGH-SCHOOL CHEMISTRY TEXTBOOKS RALPH E. DUNBAR
AND
HELEN JO BETTS
Dakota Wesleyan University, Mitchell, South Dakota
T
HOLMES,HARRY N. AND MATTERN,LOUIS W., HE general plan of this study is modeled some"Elements of chemistry," The Macmillan Co., New what after a previous study by Rendahl (1) in York, 1928. which three high-school chemistry textbooks IRWIN, FREOEPJCK C., RIVETT, BYRONJ., AND were analyzed to determine the type of mathematics TATLOCK,ORRETT, "Beginning chemistry and used in solving problems, no tabulation being made of its uses," Row Peterson & Co., Evanston, Illinois, the space devoted to these problems or the types of problems included. It is also modeled somewhat after 1927. MCPHERSON, WILLIAM AND HENDERSON, WILLIAM a study by Boles and Webb (2) in which the kind and E., "Chemistry and its uses," Ginn & Co.,New treatment of mathematics in high-school and college York, 1927. inorganic chemistry textbooks were investigated, no An analysis was made of all problems in these record being made of the number of problems, the space devoted to problems, or the types of problems twelve high-school texts, including those problems a t involved. A tabulation and study were made of twelve the ends of the several chapters, those within the cha~ters.and those in ZIDDeYIdiceS. A tabulation was high-school chemistrv ~,textbooks to determine: maie of t h e number of lines of space occupied by each (1) The number of problems contained in the twelve of the problems. From these data the space allotment texts. was determined. Then each problem was analyzed as (2) The amount of space devoted to these problems to type, e. g., reacting weight, gas law, density, etc., in the textbooks. of problems contained in these text- and also as to the operations involved in solving each (3) The types .problem, such as proportion, addition, elc. When a books. problem contained two parts, e q h of a dserent funda(4) The kind of mathematics needed for solving mental type, each was recorded as one-half unit for these problems. purposes of tabulation. In a few cases some problems A page-by-page analysis was made of the following had three Darts. each of a different t . w e , and each part textbooks: similarly was recorded as one-third unit. In amving a t a conclusion for the logical method to use in solving JAMES B., "Practical BLACK, N. HENRYAND CONANT, chemistry," The Macmillan,Co., New York, 1923. each problem, an attempt was ,made to solve each B., in the simplest and most direct way, and by the method BLANCHARD, ARTIIUR A. AND WADE, FRANIC "Foundations of chemistry," American Book Co., the student would be most likely to employ. In the solution of problems requiring several operations, each New York, 1914. BRADBURY, ROBERTH., "A tirst book in chemistry," operation was recorded as a fraction of the whole. By using this method, each numbered problem was D. Appleton & Co., New York, 1928. BROWNLEE,RAYMOND B., FULLER,ROBERTH., counted as one problem only. Also, when a problem HANCOCK,WILLIAMJ., SOHON,MICHAELD., was principally of one type a d involved essentially one AND WHITSIT,JESSE E., "First principles of chem- operation, only that one type and that one operation were recorded. From these data the findings have istry," Allyn & Bacon, NewYork, 1931. DINSMORE,ERNESTL., "Chemistry for secondary been tabulated in Table 1. An examination of the data in Table 1 shows that schools," The Laurel Book Co., New York, 1925. DULL, CHARLESE., "Modern chemistry," Henry the number of problems varies from 33 to 181, the average being 107 and the median 90 problems. This Holt & Co., New York, 1931. GORWN,NEILE., "Introductory chemistry," World would indicate that two-thirds of the books do not contain even the average number of problems of the twelve. Book Co., New York, 1930. GRAY, CARL W., SANDIFUR,CLAUDEW., AND The variation in space is from 0.34 per cent. to 3.06 per HANNA,HOWARDJ., "Fundamentals of chemis- cent., the average being 1.33 per cent. and the median try," Houghton Mifflin Co., New York, 1929. 1.27 per cent. This again shows that two-thirds of the HESSLER,JOHN C., "The first year of chemistry," books do not devote even the average percentage of space to problems. Benj. H. Sanborn & Co., New York, 1931. 187 -0-
A
.
-
Tabulations were made also of the total number of problems of each type in each textbook and of the percentages of the total number in each book belonging to eacb type. The results are tabulated in Table 2. In all, 1282 problems were studied. The total number of problems of each type and the percentage of the total of each were computed. The information is presented in Table 3. From these figures, it can be seen that problems i% volving reacting weights, weight and density calculations, gas laws, and composition make up over 90% of the total number of problems. These types of problems seem to be particularly emphasized in present highschool chemistry textbooks. Finally, the methods to be used in solving the prob-
Reorling Weighlr
Weighland
Gar
Density
Volumes
TABLE I N m s m AND SPACB ALLOTMBNT TO PROBLBMS
~ u m b ~n i n a sf of Llxcs Prob- Pmb9 lam$ lcmr P~XE
Text BI,~
Ez,";,"
97
278
38
72 174
38 34 40.25
B"*"'ee8e'
181
210 445 152* 290t 195 475 93 318.5 267 102 248 503
32 40 38 44.4 41 38 37 37 37
anant and Wade
73 I70 33 01. 91 84 FIOI~., d , ~,tt, 47 Irwin, 81 d . 92 MePherroo and Hendersoo 102 Dinsmore Dull ~~~d~~
g2K,eP
TOW Pogcr Pogcr PcrccLProbin age of lcms ~ o o k smcc 7.28 5.53 13.07
457 424 604
1.59 1.30 1.97
7.09
777
0.91
4.88 12.50 2.09 7.7 7.03 2.76 6.70 13.60
545 745 615 813 544 502 588 445
0.90 1.08 0.34 1.20 1.27 0.55 1.14 3.06
,Large type,
Corn*orition
Conrcnlrorion of Formulas Solulians
Tmpcrolurc Mclric Units Canvcrrian Colorir
Sirr(c1urc
COS~
Black and Cooant Blaneherd and Wade Bradbury Brownlee, d d . Dinsmore Dull Gordon Grar, d l el. nc.siu Holmen and Mattern Insin, d d . McPherson and Henderson
lems were studied, and the r&ults tabulated. These data are contained in Table 4. * An analysis of Table 4 shows that a total of 7 7 3 l / c problems or 60.3 per cent. of the total number of problems can be solved by proportion, 1 7 3 l / s or 13.5 per cent. by multiplication, 21g1/o or 17.1 per cent. by division, 85'/3 or 6.7 per cent. by addition, and 31 or 2.4 per cent. by subtraction.
Reacting Weight Weight and Density Gaa Volumes Camposition Formulas Metric Units Temperature Canverdon Calorie Electronic Theories or Structure Concentration of Solution Corf
promtim 59.00 B1aekandCO""t anchardand wnde Bi ~
~
F~QQWNCY OF TYPESOP PBOBLBMS EN THB TWBLVB HIOB-SCBOOL Dinrmorc C A & ~ S T RTBXTS Y
Told Number
Percrnlngc of Toto1
581.5 270.0 182.5 132.0 44.5 18.0 12.0 14.5 12.0 8.0 1.0
45.4 21.5 14.3 10.3 3.5 1.4 0.9 1.1 0.9 0.0 0.1
BY
F~NDAUBNTAL
MB O ~~S ~ ~ - - T - H~
Brownlee, r l ol.
TABLE 3 RBL&TIV&
TABLE 4 i NOYSBB AND P B ~ B N ~ OP A OPPOBLSMS B TO BB SOLVeD
~
00.8% 01.00 84.7% 118.50 d 68.2% b 107.17 59.2% 39.33 53.9%
105.84 001% 14.33 Gordon 43.4% 57.42 Gmy, d n1. 63.1% 39.00 Heuier 46.4% 28.07 H"m"and 61.0% 44.50 48.4% Imin, rl ol. 98.07 McPher~naadHendmon 00.9%
MUUC
~in;.
~ ~ i r a l i a n xion
~ddi-
sub-
lion
haclion
14.67
18.08
4.25
1.00
15.1% 4.00 5.6% 191.30 ~ 11.1% 10.75 9.3% 9.07 13.2%
18.0% 0.00 8.3% 31.17 ~ 17.9% 18.50 10.2% 14.58 20.0%
4.4% 1.00 1.4% 3.00 ~ 1.7% 23.75 13.1% 0.58 9.0%
1.1% 2.00 1.1% 14.84 8.2% 2.84 3.9%
21.75 37.17 12.4% 21.1% 0.07 8.17 20.2% 24.8% 10.07 14.92 18.3% 10.4% 14.84 20.58 17.7% 24.5% 8.17 5.17 17.4% 11.0% 11.00 21.17 n . 9 % 23.0% 29.84 23.42 18.4% 14.5%
9.17 5.2% 2.07 8.1% 1.25 1.4% 7.42 8.8% 3.07 7.8% 15.00 10.3% 7.58 4.7%
2.08 1.2% 1.17 3.0% 0.75 0.8% 2.17 2.0% 1.33 2.8% 0.33 0.4% 2.50 1.5%
_
CONCLUSIONS
The results of this study indicate that: 1. There is a wide variation in the number of problems contained in these twelve representative highschool chemistry textbooks. 2. There is a wide variation in the percentage of space devoted to problems in these high-school chemistry textbooks. 3. About two-thirds of the books studied contained less than the average number of problems and have less than the average percentage of space devoted to problems. 4. The types of problems most frequently found in
high-school chemistry textbooks are those dealmg with reacting weights, weight and density calculations, composition, and gas volumes. 5. Proportion is used more often than any other form of mathematics in solving high-school chemistry problems. Division and multiplication are used in about 30 per cent. of the operations, while the direct and exclusive use of subtraction and addition is almost negligible. LITERATURE CITED
(1) RENDA~L, J. S., "The mathematics used in solving problems in high-school chemistry," Sch. Sci. Math., 30, 683-9 hO?", ,L"u",.
(2) BOLESAND WEBB,"The mathematics of general inorganic chemistry," Sci. Educ.,14,53946 (1930).
