Good memory - Successful students - Journal of Chemical Education

Abstract: A chemical equation is often misunderstood by students as an "equation" that is used in chemistry. However, a more accurate description is t...
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DOUGLAS D. SMITH Guilford High School Rockford, Illinois 611 11

Good Memory-Successful

Student

Everv teacher realizes that no one "teaches" anyone anything. fi we "teach," it consists of our presentationof subject matter and in helpinestudents organize new material so they may retain and e;en;se new knowledge. Chemistry teachers have no problem showing students where the periodic tahle is useful in relating properties of elements to their position on the table nor including a few mnemonic devices. Most feel, however, that they cannot give students a workable, systematic method of memorization. Not so Harry Lorayne. In "Good Memory-Successful Student,"' he explains his successful "Link," "Peg Word," and "Substitute Word" systems. of Loravne's main rule is "In order to remember any. piece . information, it must be assuriatc.d, i n some ridrruiou.~u . 0 ) . with sumrt hine vou alreads k n w or remunher." I le includes chapters on thkapplicatio" of his systems to different types

of material and has six chapters directly related to chemistry.

Thew chapters inrludt: examples on memorizing iormula.;, concepts, table of common ions and charges, str&tural (cyclical and chain) formulas, and the periodic table. It is refreshing to find that Lorayne does not see memorization as a goal in itself hut as aid in making learning fun (which means possible). He writes that ". . . memory is the bridge between adsorbing ideas and applying them." Which puts the followers of his method well above Plato's divided iine: they can hope to attain wisdom. It is being suggested that the book is worthy of your perusing and ~ossihlerecommen. dation to students.

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Lorayne, Harry, "Good Memory-SuccessfulStudent," Stein and Day, Briareliff Manor, N.Y., 1973.

More Dazzle-Your-Dinner Partner Material Aeatha Christie and Arthur Conan Doyle were masters of " more than gripping, suspenseful stories. Their art includes more than ~svcholoeicalrealism and well-drawn characters. slelths of baffling, almost superhuman inBoth telligence. Why? Because both Christie and Doyle knew enough about chemistry to give the udraveling of the problem satisfying scientific validity. Readers Digest reports that Christie's "The Pale Horse" was given credit for saving ". . .the life of a 19-month old girl dying of a condition that had baffled London doctors." An alert nurse suggested the child may have thallium poisoning as the child's symptoms were similar to those described in the book. Tests confirmed thallium poisoning and the baby recovered with proper treatment. R. D. Gillaid2 points out that A. C. Doyle presented Sherlock Holmes as a first-rate chemist and cites references from 16 of Holmes' adventures to prove it. Doyle included the use of a Bunsen burner shortly after it was invented in "The Navel Treaty" and the benzidene test for blood ("A Study in Scarlet") shortly before the Adlers popularized it.

Practice in Thinking-Part

All the citations to the articles cannot he included, hut here are some of the references to Holmes found in "A Study in Scarlet." 1) He wrrkrd in a ho\pital chrmistry ]ah. 21 Holrne; hand l a , h n d a d d ~ c n touch ~ e with lahquipmpnt. I h i were "didored wirh xnmg "rids." rr, were "in\,nrishly stainrd with chemicals." 3) In discussing whether Watson should share his rooms, Holmes stated that "I generally have chemicals about, and occasianally do experiments." 4) Watson refers to Holmes as a first class chemist. 5) "He is sure to be in the laboratory," were the instructionswhen Watson was told as to where he would find Holmes. 6) Holmes' knowledge of chemistry was described as "profound." P. S. What better way to assure your cross-discipline friends that . vou appreciate their literature as much as they appreciate - .. the application of science in the same. ~

' Readers Digest, CXI, 666, p. 9, (1977). Gillard, R. D.,Educ. in Chem., 13,1, (1976).

II

In January, samples from one section of Jay A. Young's no-longer published lab manual1 were listed. That section gave instructions on how to do simple latsprocedures, from which the students were to find an explanation of what was seen by studying references. The following items are from a second section of the manual where the students are to devise their own procedure in order to solve a problem. Group A-Study of Principles 1) Prove that any salt you choose dissolves in water in the form of ions. 2) Show, forany twoelements you choose, that thelaw of multiple proportions is true for two or more compounds of these two elements. 3) Show that metals below hydrogen in the electromotive series 192 I Journal of Chemical Education

will, under certain conditions, displace hydrogen from acids. 4) Show that oxides of metals have basic properties and that oxides

of nonmetals have acidic properties. 5) By using the Dulong-Petit relation and suitable laboratory data,

determine the approximate atomic weight of any element you choose. Group B-A Study of Principles 1) Determine the value of R, the gas conatant. 2) What is the pH of a solution containing 1 mole of acetic acid and 2 moles of sodium acetate per liter? 3) Show that the presence of ammonium acetate will affect the degree of ionization of acetic acid, whereas the presence of ammonium chloride will not affect the degree of ionization of hydrochloric acid. 4) The properties of an element can often be inferred from the

Group C & D-The

PropeHies of Substances

1) What is the ionization constant of acetic acid? 2) Using data obtained in the laboratory, prepare a graph showing the densitv of liauid water as a function of its temperature over the range&xn docto 100DC. 3) Show that a fused salt will conduct an electric current. 4) Show that iodide ion is a reducing agent. 5) What is the atomic weight of magnesium? 6) Select several substances and show, hy laboratory tests, that they are all reducing agents. 7) Prove that sodium carbonate will react with calcium hydroxide. 8) Show that acetic acid reacts more slowly with zinc than does hydrochloric acid of the same molarity.

Group E & F-Qualitative

Analysis

1) What is the smallest concentration of iodine that can be detected by the starch test? 2) Show that beer contains arsenic. 3) Show that gelatine contains nitrogen. 4) Seoarate an intimate mixture of 5 s o f sodium chloride and 5 g of kcrose. As required for each problem, prepare solutions approximately 0.03 M in each ion listed. Determine, and test, methods for separatingeach ion from the others present in the same solution. 5) A1?+ Ag,+ Ba2+ 6) Cu,Zt Sn,'+ Fez+ 7) Cr207,Z- Fe,ZCAl?+ Zn2+

Grow G & H-Quantitative Analysis 1) What is the percent of acetic acid in vinegar? 2) Show that the molecular weight of ammonia is approximately 17

3) Determine the amount of citrc acid as grams per 100 ml (you may assume that all the acid present is citric acid) in a sample of citrus fruit iuice.

4) Determine the solubility product of any slightly soluble salt you choose. 5) Prove that water consists of hydrogen and oxygen in the ratia of two atoms of hydrogen t o one atom of oxygen. 6) By a procedure which requires titration, determine the carho~ dioxide content of the air in your lungs as a function of th, length of time after inhalation.

Group I & J-Preparations 1) Exercising all possible precautions to avoid loss of and eon tamination of material. . mepare mre sodium chloride rod . . salt. 21. Convert a m soluble sulfate to the corres~ondine " chloride bv tw4 different methods and confirm your results. 3) Prepare 10 ml of ethanol. 4) Prepare a few grams of coarse filamentous rayon. 5 ) Prepare a few grams of any water-insoluble Werner comple~ compound that you choose. ~

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Group K & L-Technique 1 ) Demonstrate that air has weight. 2) Show that the sum of the conductivities of a 0.1 M sodiun chloride solution and a 0.1 M silver nitrate solution is greatel than the conductivity of an equal volume of these two solution! mixed together. 3) Determine the weight of a piece of zinc without weighing it 01 any other substance on a balance or other weighing device. 4) From the standpoint of current cost and from laboratory data determine which is the best, next best, next to poorest, ant poorest antifreeze: sodium sulfate, calcium chloride, glycerine ethvl , alcohol. 5) 1)rrermme the dcn$itg of n large p i e c e d mossy tm. 6 ) .Mrasure the rrlativr humid~r)t l f the air in the Inhorarury. 7 ) Show that activated charcoal will alriurb a solute from a jolu tion. 'Young, Jay A,. "Practice in Thinking," Prentiee Hall, Englewoot Cliffs, N.J., 1958.

Volume 55, Number 3, March 1978 1 193

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