II HU(5NG DAN 0 U A N L V , S I > DUNG THUC TRANG CHAT LU0NG VA HIEU QUA SUTDUNG THIET Bl DAY HDC MON HDA HDC Jl T R M THCS I Thyc trgng chat Iflgng thilt bj dgy hgc Hda hgc THCS Thiit hi day hgc Hoa[.]
II HU(5NG DAN U A N L V , S I > DUNG THUC TRANG CHAT LU0NG VA HIEU QUA SUTDUNG THIET Bl DAY HDC MON HDA HDC Jl T R M THCS Cao Thj Phuang Chi Viin Khoa hoc Gido due Viit Nam ftng nghifm I Thyc trgng chat Iflgng thdi gian ngdn thilt bj dgy hgc Hda hgc thi nghifm THCS khdng thdnh Thiit hi day hgc Hoa hgc d edng vi li do: trudng THCS rdt phong phu vd dng nghifm nhieu chdng loai, Ndm 2005 bdt chfla chat rdn ddu thay sach dgi trd mdn Hda 16 tilp xuc hgc ldp 8, Cdc trUdng THCS chat rdn vd dflgc trang bj theo danh myc chat long qua tdi tiiieu cfla Bf GD&DT ban bl, difn tich StfdS I vi dungcu thi nghiim: hdnh, gdm cdc logi hinh chinh cdc chat tilp nhfl: tranh dnh, md hinh, mau xuc qua it, sau vat, dyng cy thi nghifm, hda 1-2 phut phdn chat thi nghifm, bdng dia, flng chat ran ban trong,,, nhiln cd thi tgo thdnh bit CPh6no h6a C M D chia logi ehinh chilm da kin 16 bdi vgy sd danh myc TBDH tdi thi nghifm thieu la dyng cy vd hda chat, khdng tilp cd the bieu dien bang sd dd diln dflgc dfldi ddy hogc qua Ve chdt lUdng phan ldn chgm; - Lfldi Sa ve hoa chat phong thi nghifm: TBDH tirfldng THCS chdt thep khdng ri, Iflgng tdt, ed till tien hanh sfl dan din tinh trgng chdy nfldc; hay hdng dyng hifu qua, nhiln van - Difn cyc eua mft s6 bf dyng nhift dg cao mdi hdn bgt edn mft sd TBDH chfla dgt cy chfla dgt ylu cdu dan din ra, rat nguy hiem; - Can hifn ylu cdu nhfl: thih trgng tiii nghifm thdnh so thilu chinh xdc, hay hdng; Ldp 8: Dyng cy difn phan edng khdng cao; - 6ng nghifm Thia xuc hod chat bang thuy nfldc hoffman khd ldm thi chat lugng khdng t6t, khdng tinh rdt khd lay hod chat va hay nghifm, tiii nghifm chi tiifle phai thuy tinh trung tinh.dl gay; Mudng ddt hod chat rat hifn dflgc ldn Id cd hifn vd dun trin nggn Ifla din sdu ldng, ldm thi nghi|m tflgng dd ri nfldc d khdp ndi cdn; Nhift ke nigu khdng xong hod chat bam chdc rat cfla difn cflc chinh xdc cho vdo nfldc sdi khd vf sinh; Kep ddt hoa chat Li do: 6ng nghifm hinh 10 cdi cho 10 kit qud; - Dyng df an khdp khdng cao, chat chfl U cd cdc khdp ndi vdi difn cy thfl tinh ddn difn khd quan Ufu bang sdt mg rat de bj ri sit; cflc dflgc gdn bdng keo khdng sdt; - Dyng cy dieu che chat 6ng hut nhd gigt qud bdp dgt ylu cdu, sfl dyng nfldc tfl chdt rdn vd chat ldng cao su chat lugng rat kem lam cho ldp keo mat tac dyng Iflgng qud ft, sau mft Hod chat: - Ddrig phoi bdo Ong tUncaoiu Kim o^ (Nhan Wi ngdy 29/12/2011) ll • TAPCHiTHI^BIGlAODgC-Sd 77 1/2012 HUONG D A N O U A N L V SLT DUNG lan nhilu tgp chat; Bgt sat khdng tinh khilt mdu khdng cdn la xam ma cd mau vang ri; - Cdn ddt, nfldc eat chat Iflgng kem; DD phenolphtalein, gidy qui chat Iflgng kim Ldp 9: Chat lugng cung cd mft so khiem khuylt nhu ldp ngodi cdn cd mgt sd nhuge diem nfla nhU: Dvmg cu di|n phan mudi an chat lugng khdng tdt, difn cflc khdng khit de bihd, lugng bay qud it khdng du de quan sat mdu sdc Vifc eung cap thiet bi nhilu cdng ty cung cap cho ede dja phflong chat Iflgng khdng ddng diu gifla cac tinh Chat lygng hod chat khdc Chang hgn nhfl: Nhdm bft, sdt bf t, ddng phoi, brom, lot nfldc cdt,,,.,Hdu nhfl chat lygng khdng ddm bao vi vgy d nhilu ndi tiln hdnh thi nghifm vdi cac hod chat khdng thdnh cdng, Vi dy d bai 12 (ldp 8) hogc bdi 23 (ldp 9) cd hUdng dan thflc hifn phdn flng gifla bft sat vd luu huynh rat ddn gidn, nhflng giao viln tiln hdnh thi nghifm tiieo sach giao khoa thi nhilu ndi khdng thdnh cdng, Dd la sdt bgt dflgc cung cap rat kem vl chat Iflgng, sdt khdng cdn mau trang xam, ma thfldng da bj den hogc mdu vdng ndu vi khdng cdn tinh khilt Hogc d bdi 18, 23 (ldp 9) ed hfldng dan tiifle hifn phdn flng nhdm chay tix)ng khdng khi, nhflng nhilu n d khdng the tiifle hifn dflgc phan flng Dd la nhdm bgt dflgc cung cap khdng phdi tinh khilt, kich thfldc hgt qua to nin khdng chdy dflgc trin nggn Ifla din cdn Hogc nhfl chat lugng eua giay qui, giay phenolphtalein, dung dich phenolphtalein cung khdng ddm bdo chat Iflgng Hogc bf difn phan nfldc theo kieu hoffman d bdi 36 (ldp 8) hodn todn khdng dap flng duge yeu cau cua sach gido khoa cy the difn phan ti If till tich cua hidro vd oxi khdng dgt 2:1 Hdn nfla bf difn phan cd phan di bang nhfla vd dflgc gan keo nhilu cho nin sau mft thdi gian ngan da bi hd, vi vdy hau hit gido viln khdng the thflc hifn dflgc thi nghifm ndy, thi nghifm hidro tac dyng vdi ddng (II) oxit bdi 31 ldp sfl dung bf dieu che chat tfl chdt ran vd chat long (Ldp 8) dng nghifm dflng chat ran 16 qua nhd nin difn tich tilp xuc gifla chat ran vd chat long qua it nin phan flng xdy chgm, ylu cau Iflgng hidro nhieu vd nhanh mdi thdnh edng nen thi nghifm ehi lam dflgc vdi dng dan hinh chfl Z cua hgc sinh cdn vdi thi nghifm bilu dien cua gido viln dng hinh try qua ldn, lugng it da khdng du de tilp xuc vdi CuO dd tiii nghifm khdng thdnh edng Mgt so nguyin nhdn ddn din chat lUdng TBDH chUa dat: Chat Iflgng tfl cung cap da chfla dgt chuan, khdng tien hdnh kilm tra nghifm thu theo dung qui II trinh giao nhgn thilt bi bdi vgy tien hdnh thi nghiem mdi phdt hifn nhflng sai sdt; Thilt bi nhgn dgt ehuan nhflng bdo quan khdng dat ylu cau; Cach sap xep bo tri thilt bi thi nghif m chua khoa hgc cy the: Kho chfla TBDH la mgt kho tong hgp tat ca cdc logi hinh thilt bi, tat ca cac mdn hgc, tfl tranh anh, dyng cy thi nghifm, md hinh, mau vat, hda chat, thgm chi ca bang dia,, ,dac bift la hda chat thi nghifm dflgc de hgp md thflc chat chung chi ed cdng dyng van chuyen, Vi thi cho nin chat Iflgng hda chat eung phan ndo bi dnh hfldng, ehung khdng cdn tinh khilt nhfl cung cap, Thyc chat TBDH eung nhfl hda chat ehi cd thdi han sfl dung nhat dinh nhflng khdng dugc tinh toan trang bj dan din tinh trgng thfla TBDH, hda chat nin hit hgn ban thdn nd da khdng cdn dgt chat lugng, I Thflc trgng hifu qua sfl dyng thiet bj dgy hgc Hda hgc trfldng THCS J Hieu qud sit dung vdi gido viin hda hgc THCS Qua khao sat cho thdy edn mgt ti If dang ke gido viln chUa ndm chac dflgc ky thugt sfl dyng TBDH, nhieu giao viln mdi ehi nam dugc ky tiiugt sfl dyng TBDH de tiln hdnh cdc tiii nghifm ddn gian, Cd the nlu mgt sd dan chflng de minh hga Vi dy, dflgc phdng van mgt so giao viln chfla nam chdc dflgc ky TAP CHi THIET BI GIAO DgC - Sd 77 -1/2012 • 23 II HlfOfNG DAN O U A N L V S C T DUNG tiiugt thflc hifn tiidnh cdng thi nghifm sdt tdc dyng vdi Iflu huynh, Nhilu gido vien chfla bilt dflgc ky thuft khfl hifn tflgng phy dif n phan v.v Li chfla thgo sfl dyng TBDH dugc trd ldi nguyin nhan theo cdp df sau: Cd sd vgt chat chfla ddp flng dflgc ylu cau; Tgp hudn TBDH chua dap flng ylu cau; Do khdng sfl dung TBDH thfldng xuyen; TBDH khdng phfl hgp hofc khd sfl dyng; Thilu y thflc rIn luyfn sfl dyng TBDH Phfldng phdp vd ky ndng sfl dyng TBDH cua gido viln chfla ddp flng dflgc yeu cdu doi mdi chfldng trinh gido dye THCS, Mgt bg phgn ddng kl cdn rat lung tung sfl dyng TBDH, chfla bilt khai thac va tan dyng hit thdng tin d TBDH, chfla chfl y sfl dyng TBDH kichtiiicbhflng thu hgc tgp cfla hgc sinh, phat huy tinh tich cyc, ehu dfng hgc tgp cua cac em, Nguyin nhan chfl ylu cua tinh hinh la gido viln chfla dflgc bdi dfldng, tgp hudn mgt each ddy du vl sfl dyng TBDH Ngay qud trinh hgc tgp d trfldng su phgm da khdng dugc chfl y rIn luyfn vl phfldng phap, ki nang sfl dyng TBDH 2.2 Hiiu qud sit dung vdi fjoc5i«/iIHCS.Kynangsfldyng TBDH cua hgc sinh cdn nhilu hgn che, chfla dapflngdflgc ylu cdu doi mdi cua chfldng trinh gido dye THCS Nguyin nhdn chu yeu cuatinhti-gngndy Id hgc sinh khdng dflgc rIn luyfn vi it cd cd hfi sfl dyng TBDH, cua hgc sinh, chfla phdt huy mfc dfl cae em hflng tiiu vdi dflgc tinh tich cflc, chu dfng vifc sfl dyng TBDH Uong qua sdng tgo hgc tgp cua trinh hgc tgp vd nhfn thdy rd tdc cdc em, Nguyin nhdn chu ylu dyng cua nd cua thyc te ndy Id GV chfla Vi dy: Nhilu hgc sinh dflgc b6i dfldng, tap hudn mft chfla bilt cdch ldp buih thu cdch bdi bdn vl ki nang sfl d xy mft thi nghifm dyng TBDH thfldng xuyIn, dieu cbl d xy; khdng bilt cdch cung nhfl qud trinh thflc hifn k^ thuft dot ndng ddo tgo ban ddu tgi trfldng Cao dng nghifm thi nghifm ddng sfl phgm cung chfla dflgc dieu ehl d xy; nhieu hgc sinh chfl ^ rIn luyfn vl phfldng khdng nhfn difn dflgc bf phap, ki ndng sfl dyng thilt bj dyng cy dilu ehl Hydro vd thu Ki ndng sfl dyng TBDH bdng hai cdch vd khdng cua HS cdn rdt kim, chfla ddp bilt cdch thu Hydro, flng dflgc ylu cdu cfla chudn III Mft s6 nguyin nhdn kiln thflc vd ky nang THCS, ddn din vifc chdt Iflgng vd suf Nguyin nhdn chu ylu eua dyng TBDH chfla dgt ylu cdu thflc tl ndy Id HS khdng 1, Cd sd vat chat d cdc dflgc ren luyfn, it cd ed hgi sfl trfldng chfla dap flng dflgc dyng thi nghifm, mac dfl cac ylu cdu, chfla cd phdng thflc em rdt hflng thfl dflgc hgc hdnh, phdng hgc bf mdn Hod nhflng tilt hgc cd sfl dyng thi hgc cho nen cdc thilt bj chfla nghifm, tgo dflgc thugn lgi cho GV sfl 4, Mgc dfl cdng tac tiiilt dyng, Sd Iflgng TBDH it cung bj da dflgc quan tdm vd chi gay dnh hfldng din tdn sd cua dgo tfl Sd gido dye din hifu GV sfl dyng, Danh myc thilt trydng cdc trfldng, dgc bift bj bdt ddu dgi trd dflgc xay mdi trfldng da cd mgt hifu dflng cho tflng ldp nin dan phd phy trdch thilt bi nhflng din tinh trgng thfla, sfl trung cdng tae thiet bj la mdi lgp gifla cdc ldp, Sd Iflgng cho ml cho nen hdu hit cdc can moi trfldng chfla dapflngdflgc bf diu chfla cd kinh nghif m ylu cdu phyc vy vifc lya chgn mua sdm Phfldng phap vd ki nang TBDH, td chflc tgp huan sfl dyng TBDH cfla GV chfla TBDH, tgo cac phong trdo dap flng dflgc yeu cdu cfla ddi tfl ldm TBDH Cac trfldng mdi cua chfldng trinh THCS THCS hdu nhfl chfla cd can Da s6 cdc GV cdn lung tung bf phy td tiii nghifm dflgc sfl dyng cdc thi nghifm ddo tgo, da sd Id cdc GV kilm md hdi phflc tgp mft chut, nhif m Day cung Id mgt anh VD nhfl cdc thi nghifm dieu hfldng khdng nhd den chdt chi oxi, hidro, metan,,,, chfla Iflgng cung nhfl hifu qua sfl bilt each sfl dyng tiii nghifm dyng TBDH Hda hgc THCS, de kich thich hflng thu hgc tgp 24 • TAP CHi T H I ^ BI GlAO DUC- Sd 77 -1/2012 ... lugng, I Thflc trgng hifu qua sfl dyng thiet bj dgy hgc Hda hgc trfldng THCS J Hieu qud sit dung vdi gido viin hda hgc THCS Qua khao sat cho thdy edn mgt ti If dang ke gido viln chUa ndm chac... cac phong trdo dap flng dflgc yeu cdu cfla ddi tfl ldm TBDH Cac trfldng mdi cua chfldng trinh THCS THCS hdu nhfl chfla cd can Da s6 cdc GV cdn lung tung bf phy td tiii nghifm dflgc sfl dyng cdc... TBDH cua hgc sinh cdn nhilu hgn che, chfla dapflngdflgc ylu cdu doi mdi cua chfldng trinh gido dye THCS Nguyin nhdn chu yeu cuatinhti-gngndy Id hgc sinh khdng dflgc rIn luyfn vi it cd cd hfi sfl