flPMATION OF SODIUM BY ELECTROLYSIS Ul SOLID SODIUM HYDROXIDE +i~dlcd by: Joseph Cipar~ck,S..J, X:ivier High School, S e ~ v 1-ork, X. Y. f&d by: Julim J , Hamerski, ~ ~ o l t h i u gJunior t ~ ~ n College, Worthiugton, Minnesota
REPARATION
emicds: A st,ick of sudiunl hydroxide. ppmtus: Electrolysis demonstr:~tion :~ppmatus wit11 flexible electrodes (or rubber 1):inds tn hold h011 tight,ly hetmen t,he elect,rodes)) copper elertrodes, 120 v d. c. source, 40-IT light, l~ulh.
~ I I C J a~ brown ?, residue forms. At the cathode, spitting and sparking shows that the sodium m&l vhich has been formed react,s vith the moisturc present. The met:tI then forn~slitt,le droplets; t,hese connect, and tr:wel from cathode to anode. This "wirc" may t,ravel all the m y to the anode, and when it, m:~kest,he connect,ion, the light glows wit,h full power.
~FMONSTRATION
Place ihe stick of sodium hydroxide h c t ~ t v e (t,he ~ !qpr d~ct,rodesof the electrolysis , app:ir:~t,us. The .?kk is 11ddby wrapping wire around the KdlIT or by ntbber lmids, A 40-w light bulh is placed in series withtl~electrodes and a direct current sonrce of about 1 % i~ ~ z~pplied. The stick of sodium hydroxide will t~egint,o " s ~ ~ e a t , " mddmps of thc caust,ic solution will drop. (Warning: h e :i heaker ready.) The light glom dimly after a h mi1111tes. Most of the drops are formed i m r the tathod?, The st,ick dries almost completely, and the k h t Ibqins to glow more brightly, getting brighter aud brighter o w :i period of ahout five minut,es. At the
REMARKS
PREPARATION
ti1 there is a rich orange cnlur, Squirt I-pcntene into t,he flask with thc atomizer unt,il t,he bro~ninecolor is gone. The immediate dis:~ppc:lrnnee of bromine color indic.at,es t,he r e w t , i o ~of~ hrominc vith the nnmturat.ed hydroc:irhun. This dcnnmstration s h o m cry nicely the t,ypic:11 reacti(~r1of the addition of bromine a t :I cnrl~on-c:irt~o~~ donble hid.
Support a 1000-ml round bottom flask :it a 30 degree ai~gl(~with a rnig qtai~d Have a source of hron~iue 13por.
Plaw I0 ml of 1-pentene
UI
an a t o m i ~ w
DEMONSTRATION
I ' m bromme \':Ip
