Cathodes lead storage battery

When a lead storage battery is supplying current, the lead in the anode grids is oxidized to Pb2+ ions, which precipitate as PbS04. At the cathode, lead dioxide is reduced to Pb2+ ions, which also precipitate as PbS04. 

In an electrochemical cell, electrical work is obtained from an oxidation-reduction reaction. For example, consider the process that occurs during the discharge of the lead storage battery (cell). Figure 9.3 shows a schematic drawing of this cell. One of the electrodes (anode)q is Pb metal and the other (cathode) is Pb02 coated on a conducting metal (Pb is usually used). The two electrodes are immersed in an aqueous sulfuric acid solution. 

Figure 9.3 The lead storage battery. The key to obtaining electrical energy from a redox chemical reaction is to physically separate the two half-cell reactions so that electrons are transferred from the anode through an external circuit to the cathode. In the process, electrical work is accomplished.

The electrical current needed to start an automobile engine is provided by a lead storage battery. This battery contains aqueous sulfuric acid in contact with two electrodes. One electrode is metallic lead, and the other is solid Pb02. Each electrode becomes coated with solid PbSOq as the battery operates. Determine the balanced half-reactions, the overall redox reaction, and the anode and cathode in this galvanic cell. 

Electrons appear as starting materials, so this half-reaction is the reduction, which takes place at the cathode. Lead(IV) oxide is an active cathode in a lead storage battery. 

In the lead storage battery, insoluble lead sulfate, PbS04(s), is produced at both the anode and cathode during cell discharge. 

Lead(IV) oxide, Pb02, is used as the cathode in a lead storage battery. Lead(IV) fluoride, PbF4, is a strong oxidizing agent (Chapter 10). Determine if either of these lead compounds is a polar molecule. 

Secondary cells are voltaic cells that can be recharged repeatedly. The lead storage battery and nickel-cadmium cell are examples of secondary cells. The lead storage battery consists of six voltaic cells. Its electrodes are lead alloy plates, which take the form of a grill, filled with spongy lead metal. The cathode consists of another group of plates filled with lead (IV) oxide, P6O2. Dilute sulfuric acid is the electrolyte of the cell. When the battery delivers a current, the lead is oxidized to lead ions, which combine with sulfate fS0 7 ions of the electrolyte to cover the lead electrode. 

Another type of rechargeable battery is the nickel-cadmium, Ni-Cd, battery, cadmium acts as an anode, and nickel (IV) oxide is reduced to nickel (II) hydroxide, Ni(0H)2, at the cathode. As in the lead storage battery, the nickel-cadmium type can be recharged indefinitely. 

How many grams of PbS04 are reduced at the cathode if you charge a lead storage battery for 1.50 h with a constant current of 10.0 A ... 

One of the six cells in a 12-V lead storage battery. The anode consists of a lead grid filled with spongy lead, and the cathode is a lead grid filled with lead dioxide. The cell also contains 38% (by mass) sulfuric acid. 

Yellow lead(II) oxide, known as litharge, is widely used to glaze ceramic ware. Lead(IV) oxide does not exist in nature, but a substance with the formula PbOj.9 can be produced in the laboratory by oxidation of lead(II) compounds in basic solution. The nonstoichiometric nature of this compound is caused by defects in the crystal structure. The crystal has some vacancies in positions where there should be oxide ions. These imperfections in the crystal (called lattice defects) make lead(IV) oxide an electrical conductor, since the oxide ions jump from hole to hole. This makes possible the use of lead(IV) oxide as an electrode (the cathode) in the lead storage battery. 

Lead storage battery a battery (used in cars) in which the anode is lead, the cathode is lead coated with lead dioxide, and the electrolyte is a sulfuric acid solution. (11.5)... 

One technically important secondary battery is the lead-acid storage battery, used in automobiles. A 12-V lead storage battery consists of six 2.0-V cells (Fig. 17.9) connected in series (cathode to anode) by an internal lead linkage and housed in a hard rubber or plastic case. In each cell the anode consists of metallic lead in porous form to maximize its contact area with the electrolyte. The cathode is of similar design, but its lead has been converted to lead dioxide. A sulfuric acid solution (37% by mass) serves as the electrolyte. 

The lead storage battery commonly used in automobiles consists of six identical cells joined together in series. Each cell has a lead anode and a cathode made of lead dioxide (Pb02) packed on a metal plate (Figure 19.9). Both the cathode and the anode are immersed in an aqueous solution of sulfuric acid, which acts as the electrolyte. The cell reactions are... 

Unlike the Leclanche cell and the mercury battery, the lead storage battery is rechargeable. Recharging the battery means reversing the normal electrochemical reaction by applying an external voltage at the cathode and the anode. (This kind of process is called electrolysis, see p. 783.) The reactions that replenish the original materials are... 

There are two kinds of electrochemical cells, voltaic (galvanic) and electrolytic. In voltaic cells, a chemical reaction spontaneously occurs to produce electrical energy. The lead storage battery and the ordinary flashlight battery are common examples of voltaic cells. In electrolytic cells, on the other hand, electrical energy is used to force a nonspontaneous chemical reaction to occur, that is, to go in the reverse direction it would in a voltaic cell. An example is the electrolysis of water. In both types of these cells, the electrode at which oxidation occurs is the anode, and that at which reduction occurs is the cathode. Voltaic cells wOl be of importance in our discussions in the next two chapters, dealing with potentiometry. Electrolytic cells are important in electrochemical methods such as voltammetry, in which electroactive substances like metal ions are reduced at an electrode to produce a measurable current by applying an appropriate potential to get the nonspontaneous reaction to occur (Cha]pter 15). The current that results from the forced electrolysis is proportional to the concentration of the electroactive substance. 

Anode Cathode Electrolysis Lead storage battery Potential Dry cell batteries Corrosion... 

A battery is a galvanic cell, or group of cells, that serves as a source of electric current. The lead storage battery has a lead anode and a cathode of lead coated with Pb02, both immersed in a solution of sulfuric acid. Dry cell batteries do not have liquid electrolytes but contain a moist paste instead. 

The ordinary automobile battery, or lead storage battery, consists of six cells connected in series (see Figure 9-3). The anode of each cell is lead, while the cathode is lead dioxide (PbOO- The electrodes are immersed in a sulfuric acid (H2SO4) solution. When you start your car, the following cell reactions take place ... 

Figure 21-17 The lead storage battery, developed in 1859, Is the oldest type of rechargeable battery. This is also called a lead-acid battery. Although not shown, the cathodes are all connected in series, as...

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