Chapter 1.

Overview

Voltaic Cells

The learning objectives of Laboratory 23 are as follows:

• Learn about voltaic cells and electrolytic cells and describe the similarities and differences between them.
• Describe the key components and flow of electrons in electrochemical reactions.
• Understand what the E_cell of a reaction indicates and how this relates to the equilibrium expression and thermodynamics.

The Department of Chemistry and Biochemistry

The Ohio State University

Intro

Electrochemistry is the study of the relationships between chemical reactions and electricity. Your laptop, iPad and cell phone use electrochemical reactions to function; without electrochemistry none of these devices would have the portability that we take for granted. Engineers, chemists and materials scientists diligently search for ways to improve technology to make these devices lighter, faster and more compact. They also look to improve their environmental impact and lessen the cost.

Building on thermodynamic concepts, we may determine the spontaneity of electrochemical reactions and learn how to manipulate these reactions to make them work. Using electricity as a driving force we can also make electrochemical reactions run uphill (in the nonspontaneous direction). This process, which is called electrolysis, has a variety of practical applications. One of the most important is electroplating, where electrolysis is used to deposit a thin layer of metal on a surface. Chrome plating is commonly used in the automobile industry to increase surface hardness, provide corrosion resistance and deliver spectacular finishes.

Procedures

In the first part of the lab you will construct voltaic cells and measure the direction and flow of electrons.

Disposal

Credits