Chapter 18 - Electrochemistry

Electrolysis

________ is used to place a thin coating of metal onto steel.

galvanic cell

A(n) ________ uses a spontaneous redox reaction to produce a current that can be used to do work.

Nobel Prize

He (Nernst) won the ________ in chemistry in 1920.

phenomenon

The ________ is caused by difficulties in transferring electrons from the species in the solution to the atoms on the electrode across the electrode- solution interface.

Cathode

________: carbon rod in contact with an oxidizing agent.

copper

Metals, such as ________, gold, silver, and platinum, are relatively difficult to oxidize.

pure metals

It is used to produce ________ such as aluminum and copper.

Oxidation

________ occurs at the anode.

half reaction

When a(n) ________ is multiplied by an integer, e° remains the same.

silicate anions

Because metals are typically such good reducing agents, most are found in nature in ores, mixtures of ionic compounds often containing oxide, sulfide, and ________.

Nernst

________ was one of the pioneers in the development of electrochemical theory and is generally given credit for first stating the third law of thermodynamics.

current flows

The actual work obtained from a cell is always less than the maximum because energy is lost through frictional heating of the wire when ________.

pH meter

A(n) ________ is a familiar example of an instrument that measures concentration using an observed potential.

Moisture

________ must be present to act as a kind of salt bridge between anodic and cathodic regions.

Aluminum

________ is one of the most abundant elements on earth, ranking third behind oxygen and silicon.

Faraday

________**: Coulombs of charge per mole of electrons.

Cathodic protection

________**: A method most often employed to protect steel in buried fuel tanks and pipelines.

battery

A(n) ________ consists of a galvanic cell or group of cells connected in series that serve as a source of direct current.

direction of electron flow

The ________ is obtained by inspecting the half- reactions and using the direction that gives a positive ecell.

Metals

________ that readily corrode can often be protected by the application of a thin coating of a metal that resists corrosion.

membrane

The ________ is superior to a diaphragm because the ________ is impermeable to anions.

Iron

________ can be protected from corrosion by coating it with paint or with a thin layer of metal such as chromium, tin, or zinc; by alloying; and by cathodic protection.

Prevention of corrosion

________ is an important way of conserving our natural resources of energy and metals.

membrane technology

Although ________ is now just becoming prominent in the United States, it is the dominant method for chlorine- alkali production in Japan.

fuel cell

A(n) ________ is a galvanic cell for which the reactants are continuously supplied.

Electrolysis

________ has great practical importance; for example, charging a battery, producing aluminum metal, and chrome plating an object are all done electrolytically.

pH meter

The ________ has three main components: a standard electrode of known potential, a special glass electrode that changes potential depending on the concentration of ions in the solution into which it is dipped, and a potentiometer that measures the potential between the electrodes.

galvanic cell

A(n) ________ consists of an oxidizing agent in one compartment that pulls electrons through a wire from a reducing agent in the other compartment.

half reaction

When a(n) ________ is reversed, the sign of e° is reversed.

galvanic cell

A(n) ________ in which both compartments have the same components but at different concentrations.