The anode is placed on the left and the cathode is placed on the right.The cell anode and cathode (half-cells) are separated by two bars or slashes, which represent a salt bridge.What is the cell notation for a voltaic cell with the following equation? Pb2+(aq) + Cd(s) → Pb(s) + Cd2+(aq) 298 kelvin temperatureĪ, b and d, a, c and d, a. Which of the following conditions are considered standard when writing electrochemical cell notation?a. Given the following information, provide the appropriate electrochemical cell notation for the following reaction:ZnSO4(aq) + Mn(s) Zn(s) + MnSO4(aq)assuming all solutions are at 1.0M, 1.0 atm and 298 K Using these rules, the notation for the cell we put together is:Ĭd (s) | Cd 2+ (aq, 0.15 M) || Ag + (aq, 0.20 M) | Ag (s)Īssign just this concept or entire chapters to your class for free. If no concentration or pressure is noted, the electrolytes in the cells are assumed to be at standard conditions (1.00 M or 1.00 atm and 298 K). If the electrolytes in the cells are not at standard conditions, concentrations and/or pressure, they are included in parentheses with the phase notation. The phase of each chemical (s, l, g, aq) is shown in parentheses.A double vertical line ( || ) represents a salt bridge or porous membrane separating the individual half-cells. A single vertical line ( | ) is drawn between two chemical species that are in different phases but in physical contact with each other (e.g., solid electrode | liquid withelectrolyte).The description of the oxidation reaction is first, and the reduction reaction is last when you read it, your eyes move in the direction of electron flow. Within a given half-cell, the reactants are specified first and the products last. The anode half-cell is described first the cathode half-cell follows.Also it is important to note that aqueous solutions should be directly next to the double lines. On the very outermost right, we have the substance that is reduced, and to the left of that single line, we see what it looks like before it is reduced. The very left of this cell diagram we have the substance that gets oxidized (for instance Zn(s)) and then on the right side of the single vertical line is what the substance looks like once it is oxidized and loses its electrons. On the left side of the double lines, you have the anode (where the oxidation takes place) and on the right side you have the cathode (where the reduction takes place). The single lines represent the phase change of the substance and the double lines represent the salt bridge that the electrons are flowing on towards the other side. With the short hand notation, it is called a "cell diagram", and we are basically representing what is occurring when you have a redox reaction. The only thing that matters in terms of sides is that the right side is the species in the cathode and the left side is the species in the anode. In lecture, Dr Lavelle also said that for the purpose of Chem 14B, it doesn't matter what order you put your specific species in on one of the sides, so I believe that Cu (s) | Cu 2+ (aq) and Cu 2+ (aq) | Cu (s) would both be accepted answers. Use a comma if they are the same phase (i.e. if there is a conducting metal in the solution like Pt). Cu (s) | Cu 2+ (aq)) or if they are different species (i.e. To separate species in one side of the reaction (cathode OR anode), you would use a single line if they are in different phases (i.e. The single line represents the interface between two species in different phases in contact with each other, but it can also be used to represent a porous disk. For a reaction using a porous disk, you can use a single line between the species present in the anode and the species in the cathode. For a cell diagram with a salt bridge, you would use a double line in between the species present in the anode and the species in the cathode to indicate the presence of the salt bridge.
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