11rnitr11I : Erwin ~ o s c h m n n n ,Drpto. d r Quimirn y Gmlogin, Univ. Agrnrin-Apnrtndo 456, Limn, P r m . T
P1 : Iloosrvnlt Alcorn. Jlichipnn Rtntr Univrrsity, 15. Lnnsing, 3lich. 48823.
PREPARATION
I'mvidr solid wdirtm hgdroxidr, iodine flnkn, nnd n lnrgr t r s t tuhr. PREPARATION
Sprinklr iodinr flnkn onto t h r lower ontddc of tho prr\.iowly moistrnrd t r s t t t ~ h r . ' IGll the tuhr n h u t . '/, 11111with wntrr nncl dis.wlvr sovrrnl grnms of SnOFl in i t . Ohsrrvr thrsr~hlimatiottof iodinr ngninst n whitr hnckgrot~nd. T h r f ~ t m r snrr intrnsr rnortph lo h r srrn hy rt rlns- of onr hunclrnl slt~clrnts. REMARKS
'I'hr s u r c n s of n Ircturr drmonstrntion lim pnrtinllv in n vivid visnnlisntion of n c n w r and riTrct rrlntionship.
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Jwrnal of Chemical Education
A topic difficult to illwt rntr wrll is hrnt rnrrpirs. I t is inconvcrtir~~t to pnss n tc-t tuhr through n r1n.u~of 10n ntr~fln~ts.I'rojrctnl thrrmomrtrr rr:tflinp nrr vrry good hut not nhvnys frnsihlr. A sr~it:lt~lr r~~dothrrmirity elemon~trntionhns hrrn rrportnl in whirh n moistc~nnlIrlork of wood is frozrn to n l ~ r n k r rin which SI14SOa is bring clissol\wl.? T h r rxnthrrmicity clrmonstrntion clrsrrihnl nhovr nlsn mnkrs twr of hrnt of solution, hut hrnts of rrnrtion cot~ldh r osrd nlt~nlly \vrll. 1
3
A little p.lywrinc r i l l help to hold thc iodinenn i h e t ~ ~ h e . llumm~S. AI.YF% .AS!>F~IF:W:IIN1%.1)rrros. (t.~di/om).
