Voltaic cells notation

This reaction, like that between Zn and Cu2+, can serve as a source of electrical energy in a voltaic cell The cell is similar to that shown in Figure 18.2 except that, in the anode compartment, a nickel electrode is surrounded by a solution of a nickel(II) salt, such as NiCl2 or NiS04. The cell notation is Ni Ni2+ Cu2+ Cu. 

On the basis of the standard redaction potentials shown above, which of the following standard cell notations below correctly represents its voltaic cell ... 

A useful shorthand notation describes the components of a voltaic cell. For exam-... 

A single vertical line represents a phase boundary. For example, Zn(s) Zn iaq) indicates that the solid Zn is a different phase from the aqueous Zn " ". A comma separates the half-cell components that are in the same phase. For example, the notation for the voltaic cell housing the reaction between I and Mn04 shown in Figure 21.6 is... 

SAMPLE PROBLEM 21.2 Describing a Voltaic Cell with Diagram and Notation... 

Problem Draw a diagram, show balanced equations, and write the notation for a voltaic cell that consists of one half-cell with a Cr bar in a Cr(N03)3 solution, another half-cell with an Ag bar in an AgN03 solution, and a KNO3 salt bridge. Measurement indicates that the Cr electrode is negative relative to the Ag electrode. 

FOLLOW-UP PROBLEM 21.2 In one compartment of a voltaic cell, a graphite rod dips into an acidic solution of K2Cr207 and Cr(N03)3 in the other compartment, a tin bar dips into a Sn(N03)2 solution. A KNO3 salt bridge joins them. The tin electrode is negative relative to the graphite. Draw a diagram of the cell, show the balanced equations, and write the cell notation. 

A voltaic cell consists of oxidation (anode) and reduction (cathode) half-cells, connected by a wire to conduct electrons and a salt bridge to maintain charge neutrality as the cell operates. Electrons move from anode (left) to cathode (right), while cations move from the salt bridge into the cathode half-cell and anions from the salt bridge into the anode half-cell. The cell notation shows the species and their phases in each half-cell, as well as the direction of current flow. 

Describe the physical makeup of a voltaic cell, and explain the direction of electron flow draw a diagram and write the notation for a voltaic cell ( 21.2) (SP 21.2) (EPs 21.13-21.23)... 

Write the cell notation for the voltaic cell that incorporates each of the following redox reactions ... 

Write and interpret the shorthand notation for voltaic cells... 

For example, the notation for the voltaic cell shown in Figure 21.5 is... 

Check Always be sure that the half-reactions and the cell reaction are balanced, the half-cells contain all components of the half-reactions, and the electron and ion flow are shown. You should be able to write the half-reactions from the cell notation as a check. Comment The diagram of a voltaic cell relies on the direction of the spontaneous reaction to give the oxidation (anode negative) and reduction (cathode positive) half-reactions. 

To fully specify a voltaic cell, it is necessary to give the concentrations of solutions or ions and the pressure of gases. In the cell notation, these are written within parentheses for each species. For example,... 

Writing the cell reaction from the cell notation Given the notation for a voltaic cell, write the overall cell reaction (EXAMPLE 20.4). Alternatively, given the cell reaction, write the cell notation. 

Write the cell notation for a voltaic ceU with the following half-reactions. 

Give the notation for a voltaic cell constructed from a hydrogen electrode (cathode) in 1.0 M HCl and a nickel electrode (anode) in 1.0 M NiS04 solution. The electrodes are connected by a salt bridge. 

A voltaic cell has an iron rod in 0.30 M iron(in) chloride solution for the cathode and a zinc rod in 0.40 M zinc sulfate solution for the anode. The half-cells are connected by a salt bridge. Write the notation for this cell. 

Give the notation for a voltaic cell that uses the reaction... 

Use the activity series to determine if an oxidation-reduction reaction is spontaneous. Write the halfreactions that occur in a voltaic cell and the cell notation. 

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