NCERT Book Class 12 Chemistry Chapter 2 Electrochemistry

Unit

Objectives
2
Electrochemistry
After studying this Unit, you will be
able to
· describe an electrochemical cell
and differentiate between galvanic Chemical reactions can be used to produce electrical energy,
conversely, electrical energy can be used to carry out chemical
and electrolytic cells;
reactions that do not proceed spontaneously.
· apply Nernst equation for
calculating the emf of galvanic cell
and define standard potential of
the cell; Electrochemistry is the study of production of
· derive relation between standard electricity from energy released during spontaneous
potential of the cell, Gibbs energy chemical reactions and the use of electrical energy
of cell reaction and its equilibrium to bring about non-spontaneous chemical
constant; transformations. The subject is of importance both
· define resistivity (r), conductivity for theoretical and practical considerations. A large
(k) and molar conductivity (✆m) of number of metals, sodium hydroxide, chlorine,
ionic solutions;
fluorine and many other chemicals are produced by
· differentiate between ionic
electrochemical methods. Batteries and fuel cells
(electrolytic) and electronic
conductivity; convert chemical energy into electrical energy and are
· describe the method for used on a large scale in various instruments and
measurement of conductivity of devices. The reactions carried out electrochemically
electrolytic solutions and can be energy efficient and less polluting. Therefore,
calculation of their molar study of electrochemistry is important for creating new
conductivity; technologies that are ecofriendly. The transmission of
· justify the variation of sensory signals through cells to brain and vice versa
conductivity and molar and communication between the cells are known to
conductivity of solutions with
have electrochemical origin. Electrochemistry, is
change in their concentration and
therefore, a very vast and interdisciplinary subject. In
define m (molar conductivity at this Unit, we will cover only some of its important
zero concentration or infinite elementary aspects.
dilution);
· enunciate Kohlrausch law and
learn its applications;
· understand quantitative aspects
of electrolysis;
· describe the construction of some
primary and secondary batteries
and fuel cells;
· explain corrosion as an
electrochemical process.