Electrochemical Cells

StudyBlue printing of Electrochemical Cells html, body, div, span, applet, object, iframe, h1, h2, h3, h4, h5, h6, p, blockquote, pre, a, abbr, acronym, address, big, cite, code, del, dfn, em, font, img, ins, kbd, q, s, samp, small, strike, strong, sub, sup, tt, var, b, u, i, center, fieldset, form, label, legend, table, caption, tbody, tfoot, thead, tr, th, td { margin: 0; padding: 0; border: 0; outline: 0; font-size: 100%; background: transparent; } body { line-height: 1; } blockquote, q { quotes: none; } blockquote:before, blockquote:after, q:before, q:after { content: ''; content: none; } /* remember to define focus styles! */ :focus { outline: 0; } /* remember to highlight inserts somehow! */ ins { text-decoration: none; } del { text-decoration: line-through; } /* tables still need 'cellspacing="0"' in the markup */ table { border-collapse: collapse; border-spacing: 0; } /* end RESET */ .header { min-width:800px; } .logo { padding:6px 20px 2px 20px; margin:0; font-size:25px; font-weight:bold; color:#808285; position:relative; border-bottom: 1px solid #c5c5c5; } .logo-blue { color:#70adc4; } .logo-desc { font-weight:normal; font-size:19px; color:#cccccc; margin-top:50px; position:absolute; display: none; } .back-button { position:absolute; top:20px; right:20px; font-size:13px; line-height:25px; color:rgb(0,175,225); font-weight:normal; } .back-button a { color:rgb(0,175,225); } .instructions { padding:0; margin:0; width:100%; position:relative; color:rgb(100,100,100); } .step-holder { border-left:1px solid #ededed; margin-left:20px; } .steps { padding:15px 0; float:left; width:24%; border-right:1px solid #ededed; text-align:center; } .steps-01 { } .steps-02 { } .steps-03 { } .steps-04 { } .label { padding:5px 10px; } .print-button { } .print-button a { background-color:rgb(0,175,225); color:white; line-height: 19px; padding:9px 8px 5px 30px; font-size:14px; text-decoration:none; background-image: url(images/printer.png); background-repeat: no-repeat; background-position: 7px 50%; -moz-border-radius: 5px; -webkit-border-radius: 5px; } .print-button a:hover { background-color:black; } .theNote .content { width: 8.0in !important; margin: 5px auto; padding:20px; background-color:white; } .theNote .header { border-bottom: 1px dashed #C8C8C8; font-size: 17px; padding: 0 0 10px; line-height: 19px; color: #00ADE1; min-width:500px; } .theNote .body { font-size: 14px; line-height: 19px; padding: 10px 0; } .theNote{ padding:6px 0; clear:both; background-color: rgb(200,200,200); } .theNote h3{ color: rgb(100,100,100); } .theNote h1, .theNote h3{ background-color:white; padding:2px 20px; width:8.0in !important; margin: 0 auto; font-size: 15px; } .theNote h1{ padding-top: 10px; font-size: 15px; } .theNote h1:first-child{ font-size: 20px; } .theNote h3 { font-size: 14px; font-weight: normal; } #options { border: 3px double #ccc; padding: 5px 12px; margin: 10px 50px 10px 20px; float: left; } #info { border-top: 1px solid #ccc; padding-top: 5px; font-style: italic; } li { margin: 5px 10px 5px 25px; } ul li { list-style: disc; } ol li { list-style: decimal; } img { border: 0; } table { clear: both; width: 100%; border: 1px solid #c5c5c5; border-width: 1px 0; margin: 0; page-break-after: always; } table#page { page-break-after: auto; } td { text-align: center; font-size: 12px; border-bottom: 1px dashed #c5c5c5; height: 1.75in; width: 50%; padding-left: 15px; } .leftside { border-right: 1px solid #cccccc; padding: 0 15px 0 0; } .bottom td { border-bottom: none; } .clearfix { clear:both; line-height:1px; height:1px; } img { max-width:80%; max-height:150px; margin:20px; } @media print {.header { display: none; } .content .header{ display:inherit; } table { border: 1px dashed #bbb; border-width: 1px 0; } .theNote{ background-color:white; } } Calculate E0 Cell he spontaneous cell reaction is the one in which the strongest oxidizing agent is reduced at the cathode and the strongest reducing agent is oxidized at the anode . For a spontaneous cell reaction, E o cell will be positive. The strongest oxidizing agent has the largest standard reduction potential. The half-cell with the largest standard reduction potential is the cathode. Therefore, the strongest oxidizing agent is Fe 3+ , and the reduction reaction in the cathode compartment is: Fe 3+ (aq) + e - Fe 2+ (aq) E o red = 0.771 V The strongest reducing agent is paired with the oxidizing agent that has the smallest standard reduction potential. Ni 2+ (aq) + 2 e - Ni (s) E o red = -0.250 V Therefore, the strongest reducing agent is Ni and the oxidation reaction in the anode compartment is: Ni (s) Ni 2+ (aq) + 2 e - E o ox = 0.250 V The oxidation potential is equal in magnitude and opposite in sign to the reduction potential. The spontaneous cell reaction is obtained by adding the two half reactions. If necessary, each half reaction is multiplied through by an integer so that the electrons will cancel. The half cell potentials represent potential differences and are NOT effected by this multiplication. 2 [ Fe 3+ (aq) + e - Fe 2+ (aq) ] E o red = 0.771 V Ni (s) Ni 2+ (aq) + 2 e - E o ox = 0.250 V 2 Fe 3+ (aq) + Ni (s) 2 Fe 2+ (aq) + Ni 2+ (aq) E o cell = 1.021 V The cell voltage is the sum of the reduction potential for the cathode reaction, and the oxidation potential for the anode reaction. E o cell = E o red (cathode) + E o ox (anode) = ( 0.771 V) + ( 0.250 V) = 1.021 V Alternatively, the cell potential can be calculated as the difference between the reduction potentials of the cathode and the anode: E o cell = E o red (cathode) - E o red (anode) = ( 0.771 V) - ( -0.250 V) = 1.021 V