Analysis of Voltaic Cell Described in the Science Textbooksof Secondary Schools
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(3) (2002. 5. 23. ) †. Analysis of Voltaic Cell Described in the Science Textbooks of Secondary Schools Tong-Hyeok Shin†, Sang-Kwon Lee, and Byung-Soon Choi* † Taejon Science High School, Taejon 305-338, Korea Department of Chemistry Education, Korea National University of Education, Chungbuk 363-791, Korea (Received May 23, 2002). . !" #$%& '( )*" %+, -.. / 0%& 12 3 45" #$%678, 9: ! ;<" => >?% 6, / @A7B '( )C" *%6.. #$ ?, D5 &E/ FG%+ )H, I J K LMN OP%+ Q RS, LT RS, U 5V W5 =X, Y RS ! -Z.. [ !" >?%L 0 )*" %6.. LT ;< ?, LT \] ^ G RS _ U ` a bc LT de a 0, Lfgh, Xi, j k l U gm" in o%& RS>p i" q -Z.. + LT &[ N rG sC" tL u .. v l LT ]F RS 5% w7xB + hy E# zW7B{ |3%} L~%, ' RS . / 5%& L~%+ )C7B / '( " *%6.. : , @ , LT, ABSTRACT. The purpose of this study was to improve the problems of the voltaic cell described in the science textbooks of secondary schools. For this purpose, the contents of science textbooks which are related to the voltaic cell were analyzed and the problems which were not explained clearly by theorems were tried to be explained by experiments, and lastly suggestions were made toward the improvements regarding the voltaic cell in the science textbooks. The findings are that there are problems on the ways of ensuring whether the voltaic cell operates properly as a chemical battery, on the explanation of why the hydrogen bubbles form at the zinc electrode, on the cell potential, on the unification of the electrode terminology used, and on the mention of the current. Solutions to the problems except the cell potential were suggested. According to the experiment, the theoretical potential was calculated by considering the potentials of redox reactions at the two electrodes of the cell and by taking into account the characteristics of the electrodes such as the work function, ionization energy, standard reduction potential, and electronegativity. The cell potential of the voltaic cell is explained by several factors. In the improved version of the textbook's introduction section to the voltaic cell, it is necessary to describe the voltaic cell historically. For the conceptual section, it should be explained in terms of the Daniel cell. Keywords: Voltaic Cell, Galvanic Cell, Electromotive Force, Science Textbook. 363.
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(11) . S, L 7B #%& #$%6.. W5 ØYv V+ .f l.. 3 (8Ø) A: W(GSâ 7G, 1998) B: W(]â 11G, 1998) C: åg:JW(â 13G, 1999) D: ñ`(sâ 12G, 1998) E: á W( â 7G, 2001) F: W(¨sâ 12G, 1998) G:
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(19) ( aâ 3G, 1998) C-i: o(â 2G, 1995) C-j: W( â 2G, 1998) C-k: áI(]¦â 2G, 1998) C-l: :J(íâ 4G, 1998).
(20) . W5 U Cuv Pb (99.99%), Zn(99.9%) Fe(99.5%)+ I ©W (Reanatarisiku Ltd.) ", Agv Pt(99.0%), © 2002, Vol. 46, No. 4. 365. K U(95%) X " W5%6.. U ØY â . ½G" =%L 0> U áX%} ¦]%6, ;< ± ?/ %L 0%& M7B hN ë (99% )" W5%6.. >m W5 B W5 Ë`(95%) `(35%)" © ;5 W5§ -+ ` (85%) !| " W5§ -+ ÓÐ# (98.5%, Duksan Pure)" W5%6.. Ë` 5ø 3.0 M $ 5ø(stock solution)7B {V Ér Û· ÷% W5%6.. E# + ;<" &'B % 6+ ,, W5 + ` U a. U >m" &( áX%} ùV W5%)·h B * w} U1 + .©/ ?%& { ú 7B Fig. 1 4Z.. ,} i7B- U W ý© ½G" =%& X]%} Q % } -Z ` U a U >m } * w7xB _ U XV+ bc{" # $ -Z.. U 0/ \]%L 0> . / ê(HSDG300-1, Hwa Shin Instruments Co.)v IïB ê(HS-337-DV3, Hwa Shin Instruments Co.)/ W 5%6.. . / ê yT $0(input impedance) 10 ΩZ78 \]10+ 10 V2 NÄ%67 Y )C" ¹% È%xB IïB ê N ¦7B W5§Z.. 0/ \] u+ 9. −2. Fig. 1. Cell used in this experiment..
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(22) 3 . 8Ø + 3 ‘±m bc’ ` v a K3. RS% -78, Table 1 2+ __ v 12 ßàá 'RS7B #%& r% !" %6.. 1 ;< Table 1 < @v l. H/ â 7Ø Ðñ % -.. ;< º/ =>, ÿ / W 5%& ! &E/ FG%+ + 2Ø(F, G), ê ?B<L/ 5%& ê" \]%+ + 5Ø(A, B, C, D, E), á ÿ v ê / @B ?%& W5 2Ø(A, C)Z.. v l ê/ @B ?% ê 4E$0 kÕ ' YN ý A5 w} §xB, ÿ / ?%& ! &E/ FG N B} .. ÿ / ?%& ;<" %, © U+ K L MN ý OP% w, I U{ .C OP .. [ ª G ÿ $0 µL u á %} ²V È%L u .. © Ðú N © U K LMN OP§+ W;{" RS%6" D I Uh K LMN OP%+ W; %&+ Ì×% w°.. #Uª 1 45 D, F, G N |3% } RS% -.. [ 8Ø Ðñ #Uª ;< Ei§V - + w°... Table 1. Inquiry activities of voltaic cell unit in science textbooks for middle school students Text-book. Inquiry Activities Electrolyte. Electrode. Volt meter. A. 10% H2SO4 10% H2SO4. Zn, Cu Fe, Cu. used used. used used. Connecting voltmeter with small bulb in series circuit Connecting voltmeter with small bulb in series circuit. orange Cu, Zn vinegar Cu, Zn dilute H2SO4 Cu+Zn, Cu+Mg. used used used. used. B. Using small bulb and circuit tester Measuring the cell potential Measuring the cell potential. C. D. 10% H2SO4 10% H2SO4. Zn Zn, Cu. 10% H2SO4. Zn, Cu. 10% H2SO4 10% H2SO4. Zn, Cu Zn, Cu Zn+Fe, Fe+Cu, Zn+Cu. 10% H2SO4 E. dilute H2SO4 dilute H2SO4. Zn, Cu Zn, Cu. F. dilute H2SO4 lemon. Zn, Cu Zn, Cu. G. dilute H2SO4 dilute H2SO4 dilute H2SO4. Zn Zn, Cu Zn, Cu. H. used. Small bulb. used. used. Additive description. Observation Observation after connecting two electrodes Observation after connecting voltmeter with small bulb in series circuit. used. Gas evolution, mass change Gas evolution, mass change, Observation of voltmeter. used. Measuring the cell potential. used used. Observing variation of metal Measuring the cell potential, Observation used used. Whether or not light small bulb Whether or not light small bulb. used. Observation of change No touching each other Whether or not light small bulb, Observing variation with time. no inquiry activity Journal of the Korean Chemical Society.
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(24) . 367. Table 2. Described concepts of voltaic cell unit in science textbooks for middle school students Textbook. Described Concepts Zn. Redox equation. Cu. Polarization. Meaning of (−) and (+) electrodes. Additive description. A. Zn loses elec- H+ ions gain elecThe cell potential is dependent on (−): oxidation trons and is oxitrons and are mentioned not mentioned the ionization difference between (+): reduction dized Zn2+ reduced to H2 gas two metals.. B. the same above. the same above. mentioned not mentioned. (−): oxidation Potential changes with electro(+): reduction lytes, concentration and metals. C. the same above. the same above. mentioned not mentioned. (−): oxidation Not mentioned (+): reduction. D. the same above. the same above. mentioned. (−): oxidation Which metal pair can the highest (+): reduction potential gain?. E. the same above. the same above. mentioned not mentioned. (−): oxidation not mentioned (+): reduction. F. the same above. the same above. mentioned. mentioned. (−): oxidation not mentioned (+): reduction. G. the same above. the same above. mentioned. mentioned. (−): oxidation (−): Materials losing electrons easily, (+): reduction (+): Materials gaining electrons well. H. the same above. the same above. mentioned. mentioned. not mentioned not mentioned. mentioned. Table 3. Inquiry activities of voltaic cell unit in integrated science textbooks for high school students Textbook. Inquiry Activities Electrolyte. Metal. Volt meter Small bulb. S-a S-b S-c. S-d. Additive description not mentioned. dilute H2SO4. Zn, Cu. 0.96 V. used. Electron reaction when connecting small bulb, Electron transfer. ". Fe, Cu. 0.46 V. used. Direction of ion migration Voltage reducing when Fe replaces Zn. dilute H2SO4. Zn, Cu. used. not used. Reactions of each metal Direction of electron transfer What is voltage if changing Zn into Al, Mg, or Fe?. (CH3COO)2Pb. Pb, Cu. not used. not used. three oranges. Zn, Cu. not used. used. S-e. Comparing before to after connecting two electrodes with copper wire. Measuring current, observation after putting 3% H2O2 into the orange when the small bulb is put out not mentioned. S-f. not mentioned. S-g. apple or pear. Zn, Cu. not used. used. S-h. strawberry. Zn, Cu. not used. used. How about the cell consisted of one metal? Which fruit is brighter in the electrochemical cell? Some strawberries in series circuit. S-i. not mentioned. S-i. not mentioned. S-k. apple or pear. S-l. 2002, Vol. 46, No. 4. Zn, Cu(Pb). used. not used. What are the potentials if metal electrodes are not equal in size? If metal electrodes are equal in size? not mentioned.
(25) . 368. Table 4. Described concepts of voltaic cell unit in integrated science textbooks for high school students Textbook. Described Concepts Redox reaction. emf (V). Polarization. Model of voltaic cell. S-a. Zn oxidation H+ reduction. 1.1. not mentioned. mentioned Describing voltaic battery historically. S-b. Zn oxidation H+ reduction. not mentioned. mentioned. mentioned. S-c. explanation by redox equation. not mentioned. mentioned. mentioned. S-d. Zn oxidation H+ reduction. 1.0. S-e. not mentioned. not mentioned. not mentioned. not Introducing voltaic battery as chemical cell mentioned. S-f. Zn oxidation H+ reduction. not mentioned. not mentioned. mentioned. S-g. not mentioned. not mentioned. not mentioned. not Describing concept by using Daniel cell mentioned. S-h. Zn oxidation H+ reduction. not mentioned. mentioned. mentioned. S-i. Zn oxidation H+ reduction. 1.09. not mentioned. mentioned Voltaic battery suggested for reference. S-j. not mentioned. not mentioned. not mentioned. not Describing chemical cell by using voltaic cell mentioned. S-k. Zn oxidation H+ reduction. not mentioned. mentioned Describing chemical cell by using voltaic cell. S-l. not mentioned. not mentioned. reducing potential during the current flow. Additive description. Anode: oxidation electrode Cathode: reduction electrode. mentioned Oxidizing H2 to water to remove polarization.. . + 3 ‘k ’ ‘ k ’ RS% -78, Table 3 ßàá, Table 4+ ' RS %& ]© .. 1 ;< 12Ø ¨= 6Ø(S-b, S-c, S-d, S-g, S-h, S-k){ % .. ßàá7B F/ %+ «B RS + 1Ø(S-b), ê" \]%+ ;<" Ei + 2Ø(S-c, S-k)Z.. ‘S-c’ + IJ ©J7B {ú ê \] in I J æ q²G#, HI, J" W5%& ê" \]>h( % -78, ‘S-k’ + IJ ©J ê \] ©J æ KJ" W5%& ê" \]> + ;< -Z.. ÿ / W5% & !" FG + 3Ø(S-d, S-g, S-h), v. Adding H2O2 as a oxidant to remove polarization. not Introducing historically mentioned. in Y/ W5 + 1Ø(S-d)Z.. > m 5ø7B ÷ Ë`5ø" W5 + 2Ø (S-b, S-c), ILM`K" W5 + 1Ø(S-d), X(¬N , W, , OL, P)" W5 + 3Ø (S-d, S-g, S-h)Z.. ô #U ª Q YN Í A 5 w7 ` K/ ùV ;< + 1Ø (S-d)Z.. ' RS" =>(Table 4), / RS%L 0> B hy + 9Ø(S-a, S-b, S-c, S-d, S-f, S-g, S-h, S-i, S-k), / zW7B{ hy + 2Ø(S-e, S-l), . B hy + 1Ø(S-j)Z.. LT" < + 3Ø(S-a, S-d, S-i), #U ª" RS + 6Ø(S-b, S-c, S-d, S-h, S-k, S-l), 3Ø(S-e, S-j, S-l) / â Ð Journal of the Korean Chemical Society.
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(27) . 369. Table 5. Inquiry activities of voltaic cell unit in chemistryII textbooks for high school students Text-book. Inquiry Activities Electrolyte. C-a. Metal. Voltmeter. not mentioned for voltaic cell. C-b C-c. not mentioned 1.0 M HCl. C-d. C-e. Additive discription Inquiry activity for Daniel cell. Zn, Cu. used. not mentioned for voltaic cell. 0.01 M H2SO4. Zn Cu Zn, Cu Zn, Cu Zn, Ag. Measuring the cell potentials in 0.5 M and 1.0 M HCl Inquiry activity for Daniel cell Inquiry activity for Daniel cell. used used. Observation Observation Observation after connecting Measuring the cell potential after connection with Cu wire Measuring the cell potential after connection with Cu wire. C-f. not mentioned for voltaic cell. Inquiry activity for Daniel cell. C-g. not mentioned for voltaic cell. Inquiry activity for Daniel cell. C-h. not mentioned for voltaic cell. Inquiry activity for Daniel cell. C-i. orange. Zn, Cu. used. Inquiry activity for Daniel cell. C-j. lemon. Zn, Cu Zn, Pb. used. Measuring the cell potential. C-k. not mentioned for voltaic cell. Inquiry activity for Daniel cell. C-l. not mentioned for voltaic cell. Inquiry activity for Daniel cell. ú + bcЫ" R7B RS% -Z.. © ` U" ÏU ô+ (−)U, a U" fU ô+ (+)U7B 4 -Z.. S = X 5V W5 Ér%. P_§Z.. II . II + 3 ‘ bc’ ‘` a bc’ RS % -.. Table 5 ßàá 1 ; < 4ØY(C-c, C-e, C-i, C-j) { % -78, 7h/ ½ ð LT" \] + 1Ø(C-c), I ©U æ I U ô+ I KU" W5%& LT" \] + 2Ø(C-e, C-j)Z78 >m 5ø7B+ `, Ë`, P, T 7B 4Ø N Ðñ ¶U.. © . ßàá{ ; + 7Ø(Ca, C-d, C-f, C-g, C-h, C-k, C-l)Z78, 2Ø(C-c, Ci) + ;< ) V . ; <" V%& ;%6, 1Ø(C-b) { ß àá BZ.. 12Ø ' RS" =>(Table 6), / RS%L 0> B RS 2002, Vol. 46, No. 4. + 5Ø(C-a, C-c, C-e, C-g, C-i), . Bh RS + 3Ø(C-a, C-e, C-I)Z.. © 5Ø / â 7Ø + . B ©/ RS%6.. zW7B{ / RS + 3Ø(C-b, C-j, C-l)Z.. IJ ©J" ÷ Ë` WN B X w} L .f, ñ åþJ" h(7 B ?%& {ú 8 í · RS + ‘C-b’, í / R7B < + ‘C-j’Z.. ©, 1796 N Kå± æ YZ # / ñ åþJ ç£ {ú í · RS + ‘C-l’Z.. ` U a U XV+ bc " RS + 6Ø(C-a, C-b, C-c, C-e, C-g, C-i) Z, ‘C-b’ + U #U ª" RS%L 0> |3 %6.. 6Ø L T" =>, ‘C-a’+ 0.76 V, ‘C-b’ + 1.1 V, © 1.1 V · RS + 3Ø (C-e, C-g, C-i)Z, ‘C-c’+ LT Ì× BZ.. © #U ª, >.
(28) . 370. Table 6. Described concepts of voltaic cell unit in chemistryII textbooks for high school students Described Concepts Textbook. Voltaic cell. Description of chemical cell. Explanation of reaction. emf (V). Polarization. Anode. Cathode. Principle explanation. C-a. mentioned. 0.76. mentioned. (−). (+). voltaic & Daniel cell. Potential reducing by local current. C-b. mentioned. 1.1. mentioned. (−). (+). Daniel cell. Describing voltaic battery historically. C-c. mentioned. not mentioned. not mentioned. (−). (+). voltaic cell. HCl used. C-d. not mentioned. not mentioned. not mentioned. (−). (+). Daniel cell. C-e. mentioned. 1.1. mentioned. C-f. not mentioned. not mentioned. not mentioned. (−). C-g. mentioned. 1.1. mentioned. C-h. not mentioned. not mentioned. C-i. mentioned. C-j. Additive description. voltaic & Daniel cell. The cell potential Zn-Ag > Zn-Cu > Zn-Fe. (+). Daniel cell. Describing the cell potential as emf. (−). (+). voltaic cell. Potential reducing to 0.4 V by polarization. not mentioned. (−). (+). Daniel cell. Describing voltaic battery historically. 1.1. mentioned. (−). (+). not mentioned. not mentioned. not mentioned. (−). (+). Daniel cell. Introduction of the first voltaic cell. C-k. not mentioned. not mentioned. not mentioned. (−). (+). Daniel cell. Voltaic cell for prerequisite learning. C-l. not mentioned. not mentioned. not mentioned. (−). (+). Daniel cell. Voltaic cell for science history. positive negative. RS% -+ 6Ø ‘C-c’/ â 5Ø RS% -, LT [V + QB ª â I U þ ±B V-+ GL J yN (−) Zn\H SO \Fe (+) v l E / «g%L u · RS + 1Ø(C-a) Z.. ©, ` U a U" _ _ (−)U, (+)U· 11Ø + RS% -7 , ‘C-e’+ ÏU, fU· RS% -.. 2. 4. . + ` U" ÏU ô+ (−)U, a U" fU ô+ (+)U7B 4 -.. E# + (−)U, (+)U7B d% +,, U bc" %+ 1!+ ` U a. voltaic & Daniel Potential reducing to 0.4 V by polarcell ization. U 5VB W5%+ ) ]%, / W 5%& âE LL/ Dáð+ 1!+ (−)U^, (+)U^ 1ã -.. ÏU, fU" W5%+ 8 + a U(cathode)/ fU, ` U(anode) ÏU 7B _z> W5%L u G, 5VN G%+ @v ; U (−)U, (+)U bN §xB Õ` á .. II ÏU, fU ·+ 5V/ W5 8N -+,(C-e), L 1 2 45" .a u W5% w+ b.. ô (−) U, (+)Uh v L#>+ @c} §V h ¡" Nd N -.. L bc 1ã " e+ y+ (−)U (+)U7B W 5%L.+ ` U, a U7B 5V/ =X%& W5%+ b. J3 .. Journal of the Korean Chemical Society.
(29)
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(35) ]+ ¤f7B II '" .² -.. A5+ Y+ UW ý©, U d >m 7hv 1N -.. [ ê [ ½ + 1B X]%.. UW ý©N N2k(, U d l"(, © >m 7hN m( j á nV x B $0 DId Y^ oN%} .. M5` 5% 5ø(pH 2.20), T p¢(pH 2.36)B {ú v T q ;< / &¾" u, ê L N ÐñN &r%67 Y+ M5` N µ, .f T p¢, T 14. 2002, Vol. 46, No. 4. 371. Z.. T p¢B {ú YN T . ) µ} ¬+ Q+ T + j á LEs u wL u Z.. 7Þ
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(38) ] ` a 3 â @w%. P_ .. ! "#. B Dá%+ &E/ FG%L 0> ê \], Y \], ÿ ! FG )H " W5%6+,, x yB FG -+ )H b. P_ .. © êv ÿ/ in @B ?%& R7B < N -Z+,(Av C), v l )H7B ê \] - { ]F 0/ \] B"D)[ ÿh ¯ w+.. ÿ + = 1.5 V5 W5§+, + 0.9 V ]h 9 ê" 4xB ¯ w+.. .©/ W5%+ . / ñ ' {V @ B ?% Oz.¬{ E$(buzzer) " W5% NÄ%.. } -+ | Ý Oz.¬{ }~+ 1.8 V ê Ér% Y+ U } KÐ%xB .© $0 N § w+.. . ñ '/ @B ?% M ê 2.2 VN §xB } 1§Vm.. $%& '( ) *+& ,- .. ©J K LMN OP§+ . IJ K LM N ) OP.. $0 µxB I J ` v a bc XVL L u IJ K LMN OP.. + + % Ì×% w°.. [ [ W;" Ì×>p % ¬o L '" > %+, ¿G )H7B W5 -. P_.. 15. 16.
(39) . 372. ÷ Ë` ` 5ø Iåþ" ù7 K LMN OP% &L ©(" ?%& ©( ò " ` W ©h KLMN OP.. ß;<" =%& [ ª" 1% I U Pg N ©(" =%& Kj ? Ù%& ©h KLMN Pg§Z.+ W;" q } i7B- ñ UWv 5ø" => M L? BN g§V YN A.+ W;" > .. K LMN OP% B W5%+, N -7xB KLM/ B+ )* > P} »/ %h( %, * >?H7B . / K' .f, bò bc U 0Þ/ %+ )H L û" RS%+ @w %. P_.. Barral [ ;<" & IÕv RS" % w P _N N + " à5%& ª" RS%h( ´ P c" #Y%& N N -+ &[ Ø Y ¬G" ® + W%+ @N µ.. / 01 . @ LT(electromotive force, emf) ‘YN A5 w+ ¦"% U| 0Þ(open-circuit potential) ’/ 4+ 5VB 0v l GB W5 .. @ ñ bò W \] 0Þ+ ! % h(charge density) u I h
(40) %+ ñ åþ >m 5ø W 0Þ Ù.. Ðú + LT \]" êB %6+,, L ; 0/ \] u = ‘ê(voltmeter)’v+ . ‘0Þ(potentiometer)’ / W5.. º+ yT$0 ëL u YN A5 w+ ê" \] -.. yT$0" µ}%& ¹ D ê/ W 5% LL \]¬Þ/ Õ { ]F L T" \] -.. Özkaya + &W 92S" 7B R ¦W 1S" â% LT ]/ ÍÈ · %6, 35S êv 0Þ LÄ Þ!" G% È%6.. Ðú LT \] 12 ?B RSE# ‘ê’+ ‘0Þ’B @cVdp .. \]º $0 µ w., YN \]ºB A5} §V ê%N XV { ê" 4 oN} .. D{ I·, N D᧠7 hN ½%} §+, ê" \] u 7hh 17. 18. 19. sC" } .. / V, 4E$0 10 Ω f êB 0Þ/ \]%+ 8, 0 N 1.00 V·  á%+ + 1.0410 mole/s xB ê \] Pg§+ j 7hN V 7h Gº+ sC" Õ -.. Xb êB+ LT" ]F%} \] %L Vu.. 3 LT 8Cg·ú G &, ¼ OG L bc" =%& YN A5} .+ ]gG 1! à5>p .. 23 / 4 56 . ¨= v 4Ø II + LT ûG RS B 1.1 V· &d -, ‘C-a’ + 0.76 V· B %} &d -+ ,, ûG ` ý%& B l} &dp .. [ ‘S-b’ ß ;< ?+ ¬o 1.1 V N2 0.96 VB \]§Z.. v l LT . ./D)[ \] ? R S ]F% wI PD{ I· Wh U bc > Vo" üç -.. . + LT \] ?/ Nernst 7B >$ - {, + l )H7B SF%} >$§ w+ ! -.. LT bc ÂLEÀ × [V + Q/ E# + ©U OP%+ #U ª7B RS%678, IU E i GC ± E / «g%+ 7B in . + ‘C-a’ DZ.. + 4E N -+ Lk / 4E KÐ> ©+ L) ª" 4+,, G K ê N N µ. qod -.. >m 5ø ± j -+ 8 åþ ± IU $:§+ 8h, $: åþ 0 N IU. (+) 0 E 0/ «g%& K LMN OP% I © 5> .. ± G Cu, Fe, Ni, Co, Mg, As, Sb K ê 9L u L ) G .. s + IU" 10% HgCl HgB I ¤©%& I U E «g" Kð ©U" N %& CuOB ¤©% #Uª" K Z.. HgB I ¤© IU CuOB d ¤© Cu U" W5%6" u 1.11 VB ê YN N ë} \]§Z78, I IU 13. −18. 20. 21. 2. Journal of the Korean Chemical Society.
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(42) . 373. Table 7. Various properties of electrodes used in this experiment Properties Standard reduction potential (V) Electronegativity Ionization energy (kJ/mol) Work function (eV) Electrical conductivity (Ω−1m−1). Electrodes Zn. Fe. Pb. Cu. Ag. Pt. -0.76 1.65 906 3.63 16.9. -0.44 1.83 762 4.37 11.2. -0.13 2.10 716 4.25 4.8. 0.34 1.90 746 4.48 60.7. 0.80 1.93 731 4.52 62.9. 1.20 2.28 870 5.84 9.4. ©U" W5¾" u+ 1.05 V, © IU ©U" W5%6" uN 0.89 VB N 9} \]§Z.. I ¤© IU+ LEN ý OP% w°.. v l ?/ ØÙ%, I © U ENbc" X7ð wh( ¤º/ %+ 8 I ` %+ U 0v K OP" Le7B %+ a U 0 ÞN LT" ?] .+ P_+ .5} ë} +,, I © U g Ðñ LT sC " Gº+ 7B P_ -.. : !" #$ %&' () ` U a U7B W5 ñ å þ g LT 1 1/ e+.. T ` a U" q ê" \] ;<?(Zn/Cu: 0.979 V, Zn/C: 0.989 V, Mg/Cu: 1.5~1.6 V), ` U " @Z" u ê µ} ½¾ { + .5} a U" @Z" uh ê | ½ N -Z .. U de a 0, Lfgh, j k , Lhh, Xi åþ g LT Gº + sC" qIL 0> åþ ØY Û· ` U a U7B 16 / g%& LT" \]%6.. &L W5 åþ g Table 7 4Z \] LT ?+ Table 8 4Z.. ;< >m 7h+ 1.0 MB %678 Ë`, ÓÐ#, `, ` " W5% & &%6.. åþ ØY Û· .Ï%} LT ½ %+ " q -78, W5 >m Û· 8Cg & r%6 { LT µL+ .5} .. Zn-Cu B ²Vm «G LT 0.96 VB \]§V, ‘S-b’ ß ;< ?v Xº%6. 78 Ë` 5ø 7h/ 1.0×10 M~3.0 MB ½ %6" u \] LT 0.90~0.96 VB Kj 7 hv 1B ý X]%6.. Table 7 8 ?/ ØÙ%& dea 0, L fgh, j k , Xi, © Lhh Û LT ½ / &%6.. 7 89& :; / <. a U bc &% + w+ &àg U ¤¥ W5 .. ` U" X]%} %, 1.0 M Ë` >m a U de a 0v LT 1 / Fig. 2 4Z.. S~v l a U de a 0N oN(, Q U a bc " X7 -+ ÄT Û· LTh oN.+ W;.. + S~ LkLN . µ w7x B Swartling ?v 8Cg &r%. & −3. 15. Table 8. Average cell potentials of various voltaic cells Cell Potential (V). 15. 2002, Vol. 46, No. 4. Electrodes Zn-Cu Pb-Cu Fe-Cu Zn-Ag Pb-Ag Fe-Ag Zn-Pt Pb-Pt Fe-Pt Zn-C Pb-C Fe-C Zn-Pb Zn-Fe Pb-Fe. 1.0 M H2SO4. 1.0 M HCl. 1.0 M KOH. 1.0 M NH4Cl. 0.96 0.17 0.47 1.15 0.30 0.72 1.45 0.66 1.00 1.30 0.54 0.95 0.79 0.41 0.38. 0.81 0.32 0.22 1.02 0.56 0.46 1.29 0.92 0.83 1.11 0.45 0.37 0.51 0.60 0.10. 1.23 0.54 0.04 1.65 0.93 0.34 1.43 0.73 0.25 1.27 0.55 0.06 0.72 1.22 0.44. 1.02 0.37 0.50 1.14 0.60 0.64 1.49 0.89 0.97 1.50 0.91 0.95 0.64 0.60 0.10.
(43) 374. . {, Zn-Cuv Zn-C ñ ØY ;<{ ¾7xB ? F Et u F; &+ NÄ%.. 3 a U+ ` U Pg N 0N ë a U7B á% Kj bc%& K N Pg§+ =BB{ W5§+ I·+ .. a U de a 0N ( LTh | oN.+ W;" q} §Z.. =>?& :; / <. Lfgh+ / VL+ ÄTxB a U a bc s C" g 7B P_ .. S ` U X]%} %, 1.0 M Ë` >m" W5¾" u a U Lfghv LT 1/ Fig. 3 4Z.. LfghN oN% LTh oN%67 >m ` 5øG 8+ [ 8Cg . K V.. E# 8 gm LT µL+ a U LfghN ( oN%6.. 6@&A & :; / <. j k + ` §+ ]hv 12§L u , a U áX U" W5% ` U ØY Û· LT ½ / Fig. 4 4Z.. ` U j k N oN% LTh oN%6 {, ` >m 5ø+ K J . 8C .. E# 8 ` U j k N ( LT oN%6.. BC'& :; / <. Xi+ ±m 4 / 7B V4+ , Ér íK X.. S ` U X]%} %, 1.0 M Ë` >m " W5%6" ua U Xiv LT 1 + Fig. 5 4Z.. E# 8 a U. Fig. 2. Variation of cell potential with reduction potential of cathode in 1.0 M H2SO4.. Fig. 3. Variation of cell potential with electronegativity of cathode in 1.0 M H2SO4.. XiN 'm( LT ' + 8C B .. ??& :; / <. Lhh+ / Í ¶ -+ UX( LT 7 B P_%6.. S áX ` U" W5% a. U Lhh Û LT" => ?, X bG 8Cg" Oä% È%6.. Û·, _ U Lhh+ LT µL sC" w+. + ?/ ;Z.. + åþ Lhh Þ .+ >m 5ø LhhN ) f sC" G .. D>6 /& EFG HI. ;< ?, LT _ U ` a bc ñ U g h%6.. åþ ` §+ ` U å þ ØY Û· LT f sC" G, K j a §+ a U ©N $:§+ bc X. Fig. 4. Variation of cell potential with ionization energy of anode in 1.0 M H2SO4. Journal of the Korean Chemical Society.
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(45) . Fig. 5. Variation of cell potential with work function of cathode in 1.0 M H2SO4.. V wIh | sC" G.. [ LT" ½ ð+ , sC" + U gm de a 0, Lfgh, Xi, j k Z.. ;< \] LT 0.96 VB ` a. bc dea 0BEÀ ^G 0.76 Vv + ÞN -7xB [ U g" o>p % +,, P}+ %LN w.. [ xB >+ zW7B{ hy%ú ô +, K LM OP 1" =%& v j 7B N g6 -.+ © RS FB{ W5>p .. ßàá+ LT" * ]%} \] -+ . / © XPà } -+
(46) FB {V ;<%, ©v 1 L '" RS>p . J3 ...
(47) + !" #$%, 9: ! >? )*" ¡%& / @A7B '( )C" %6.. ! #$ ?, ßàá+ IU K LM OP W; m~§V- w°78 B Dá§+ / FG%+ ¢ )H § È%6.. ' RS+ ` U a U 5V =Xg , U0 dª ) =X g , Y RS G£, 0 \] LL G ?&v LT û ? 2002, Vol. 46, No. 4. 375. !, © ;< ?vh Xº% w+ ! 9: §Z.. [ ! >? )*7B ßàá+ I J K LMN OP%+ W;" Ì×% © U ?% á %& KLMN © Uh OP.+ W;BEÀ Dá © / RS%} %+ H Ér%8, N Dá %+ + 9 T7Bh } Dá§+ Oz.¬ { E$ " W5%+ Ér%.. 'RS + =X 5Vv dª )" %6 LT \ ] yT$0 f ‘0Þ’/ W5%& \]>p.. LT \] ?N Nernst 7B >$ § w+ ! ;<" V%& >?" h%6 .. ;< ?, LT _ U ` a. bc ñ U g h%6.. ` U åþ ØY Û· LT f sC" G, K j a §+ a Uh åþ ØY Û·| sC" G.. LT ½ sC" Gº+ U gm de a 0, Lfgh, Xi, j k Z.. ;< \] LT [ g" o>p %+,, P} + %LN w7xB + hy E# zW7B{ |3%} RS%, L L © ', © ßàá . / W5%+ b. J3 ... 1. Bojczuk, M. School Sci. Rev. 1982, 64, 545. 2. Finley, F. N.; Stewart, J.; Yarroch, W. L. Sci. Educ. 1982, 66, 531. 3. Butts. B.; Smith. R. Aust. Sci. Teach. J. 1987, 32, 45. 4. Allsop, R. T.; George, N. H. Educ. Chem. 1982, 19, 57. 5. Birss, V. I.; Truax, R. J. Chem. Educ. 2002, 79, 735. 6. Garnett, P. J.; Treagust, D. F. Int. J. Sci. Educ. 1990, 12, 147. 7. Garnett, P. J.; Treagust, D. F. J. Res. Sci. Teach. 1992, 29, 121. 8. Garnett, P. J.; Treagust, D. F. J. Res. Sci. Teach. 1992, 29, 1079. 9. Ogude, A. N.; Bradly, J. D. J. Chem. Educ. 1994, 71, 29. 10. Sanger, M. J.; Greenbowe, T. J. J. Res. Sci. Teach. 1997, 34, 377. 11. Kim, Y. M.; Park, S. J. J. Kor Phys. Soc. Phys. Educ..
(48) 376. . 1992, 10, 39. 12. Kim, Y. M.; Park Y. H.; Park, S. J. J. Kor. Assoc. Res. Sci. Educ. 1990, 10, 47. 13. Kim, Y. M.; Kwon, S. K. J. Kor. Assoc. Res. Sci. Educ. 1992, 12, 61. 14. Hill, G.; Holman, J.; Lazonby, J.; Raffan, J.; Waddington, D. In Chemistry: The Salter's Approach; Heinemann Educational Books Ltd: Oxford, U.K., 1990, p 167. 15. Swartling, D. J.; Morgan, C. J. Chem. Educ. 1998, 75, 181. 16. Shin C. H.; Conceptions of Redox Reaction According to the Cognitive Levels of Korean Middle School Students. M. Ed. Thesis, Korea National University of. Education, 1999. 17. Barral, F. L.; Fernandez, E. G.-R.; Otero, J. R. G. J. Chem. Educ. 1992, 69, 655. 18. Bard, A. J.; Faulkner, L. R. In Electrochemical Methods: Fundamentals and Applications; 2nd ed.; John Wiley & Sons, Inc.: New York, U.S.A., 2001; p 5. 19. Özkaya, A. R. J. Chem. Educ. 2002, 79, 735. 20. Kim, Y. J. In Modern Electrochemistry and Technology; Seoul University Press; Seoul, Korea, 1985, p 324. 21. Song, Y. B. A Study on Analysis and Improvement of Chemical Experiments in the Middle School: with Focus on the Theme of Four Experiments. M. Ed. Thesis, Korea National University of Education, 2000.. Journal of the Korean Chemical Society.
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