The Elements of Qualitative Analysis. W. A. The directions for each

valence, atomic weight. of the more common elements. solubilities of common compoundn, sapm tension, thermometer conversion table, met&-English cquiva...
0 downloads 11 Views 662KB Size
The Elements of Qualitative Analysis. W. A. NouSs. Seventh edition, revised, in collaboration with the author, by J. H. Resou. ~ o r k ,1923. PP. ~ ~ n ~r oy i & t co., ~ e w vi 128. 13% X 21 cm. 61.50.

+

The original purpose 01 this widely "red manual. to prvvide beginnen with explicit directions for manipulations, has been retained. The general Corm is t h a t of the earlier editions The direction. for certain procedures have been clarified or am~lifledas a result of experience with Parse c1assee A few distinct departures fmm the procedures or the previous edition have been made. The rations of the tin mxb-group arc separated by ammatrivm carbonate and aluminum, a method which experience has show" t o give better iesuits in the hands of elementary students than separation by varied concentration5 of hydrachlorlc arid. Nickel ie tested far by dimethylslyoxime and cobalt by thiocyanate (Vogel's reaction) thus obviating the use of cyanide. Potxrsium is ~reeipitntedby perchloric acid and sodium by Euorilieic acid, only secondary importance being attached Lo the Same tests. I n the detection of anions these are tested for, ss far P O ~ S in ~ ~the I ~ , removing cations of heavy metals. The cations present having been determined, this information is combined with the solubility relations of the original substance t o deduce what anions may be present. The changes noted all make for increared urefvloess and will be wcleamed by teachers who have used the book in previous editions. Ioniration, maro-action, t h e salubility-pmduet principle and the colloidal state are briefly diseusned io an introductory chapter. Reference t o these matter. lo infrequent in the rubpeqvent pages and their c m p h a ~ i sor omirrion left t o the instructor's discretion. As in the earlier edition., the typography i. excellent and erron notably few. A. R. MIDDLZIOX

The directions for each experiment are printed on one ride of the leaf, only, leaving a blank page opposite the directions for each experiment and i t is evidently the intention of t h e authors t h a t the blank page be used for answering the rupplementary questions relating t o each experiment. The directions for performing n given experiment are clear and concise and it should be possible for most students t o follow t h e directions without an undue amount of additional help on the part of the teacher. With each experiment is found n number of speeifiequestian. which call attcmion t o t h e important observations t o be made and theeondusiona which should be drawn. I n addition to the specific questions, there arc a number of genera1 questions rr1sting t o each experiment which are intended to bring out certain applications of the experiment in question. Some of the9e questions are pretty good. Mort ofthem, however, eao be answered by the average student only by reference t o textbooks since they d o not in m m t eases refer t o actual experiences common t o m m t boys and girls. A t the end of t h e book are s i r tables: symbok, valence, atomic weight. of the more common elements. solubilities of common compoundn, s a p m tension, thermometer conversion table, met&-English cquivaleots and a valence chart. The reviewer is unable t o observe anything panieularlv b e w in t h e e experiments. It would seem t h a t the experiments should increasingly require more independent work on t h e part of the stvdent if he is expected t o gain as t h e result of lnharatorv As a m a t t s of . exoerience. . fact, i t appearr t h a t the student is given prtically t h e same amount of detailed help in each of the experiments. In other wards, t h e re9"irements placed upon the student d o not increase in difficulty as he works his way through the list of experiments. ~ a e hexperiment eonrtitutes an additional aeeumv1ntion of facts without provision for an inveared independent laboratom ability. H ~ R A. Y CARPBNYBR

MARTIN MewFordham Publishing Co.. New York. 1024. 61 pp. 20.5 x 265cm. $ 0 6 C with binder plus $0.25.

B i o l o a and Bomao Welfare. J. E. Waaoounm A. B. HUNT. Macmillan Company, New York. 1924. xii 585 p a g e . 13.5 X 20 em.

IIour pages are devoted t o preface, index of experiment. and diagrams of apparatu.. The preface stater t h a t t h e experiment sheets are t o be available in loose-leaf form whereas t h e voltune rvbmitted is in permanent binding. The index to experiments shows 59 titles which include the more frequently used laboratory erpcrimeots for elementary genera1 chemistry.

A review of a text on biology may seem out of place in a chemical journal but this book warrants some mention here. The reviewer is no authority on biology ra daes not venture any opinions on t h e biological phase of t h e hook heyond the statement t h a t t h e motive of t h e text as set forth in the preface seem. very sensible and t h e book look^ v e r y interesting.

Chemistry Experiment Sheets.

DBL A N D MILTON B. BRUND&GE.

+

$1.68.