Write equations for the half-reactions that occur at the anode and cathode for the electrolysis of each aqueous solution:
a. Ni(NO3)2(aq) b. KCl(aq) c. CuBr2(aq)
Chapter2 Thursday,August31,2017 5:56PM AtomsandElements • Matterisneithercreatednordestroyed • Inchemicalreactions,whatyoustartwithinmass,youendupwith ReactantsProducts LawofDefiniteProportions • Allsamplesofagivencompound,regardlessofthesourceorhowtheywere prepared,willhavethesameproportionsoftheirconstituentelements • Acompoundisdecomposedtoitsconstituentelementsandproduced25.6gofO and9.60gofC.Asecondsampleofthesamecompoundproduced21.6gO.How muchcarbonisinthesecondsample (25.6gO/9.60gC)=(21.6gO/xgC)CrossMultiply… (207.36/25.6)=8.1(25.6gx/25.6)x=8.10gC LawofMultipleProportions • Musthave2compounds(CO toCO)2H OtoH O2) 2 2 • When2elements(A&B)formtowdifferentcompounds(AB&A 2)Bthemassesof elementthatcombinewith1gofAcanbeexpressedasaratioofsmallwhole numbers • Dalton'sAtomicTheory 1) Eachelementiscomposedoftiny,indestructibleparticlescalledatoms 2) Allatomsofagivenelementhavethesamemassandotherpropertiesthat distinguishthemfromtheatomsofotherelements 3) *Atomscombineinsimple,wholenumberratiostoformcompounds 4) Atomsofoneelementcannotchangeintoatomsofanotherelement • J.J.Thompson(CathodeRayTube) - Particleswithanegativecharge - Mass-to-changeratiois- 1.76x10 coulombspergra
