Vernier Software and Technology
Vernier Software & Technology

Beer's Law Investigations

Figure from experiment 11 from Investigating Chemistry through Inquiry

Introduction

The primary objective of this Preliminary Activity is to determine the concentration of an unknown copper (II) sulfate solution. You will use a Colorimeter (a side view is shown above). In this device, red light from the LED light source will pass through the solution and strike a photocell. The CuSO4 solution used in this experiment is blue. A higher concentration of the colored solution absorbs more light (and transmits less) than a solution of lower concentration. The Colorimeter monitors the light received by the photocell as percent transmittance.

You will prepare five copper (II) sulfate solutions of known concentration (standard solutions). Each solution is transferred to a small, rectangular cuvette that is placed into the Colorimeter. The amount of light that penetrates the solution and strikes the photocell is used to compute the absorbance of each solution. When you graph absorbance vs. concentration for the standard solutions, a direct relationship should result. The direct relationship between absorbance and concentration for a solution is known as Beer’s law.

Objectives

The primary objective of this Preliminary Activity is to determine the concentration of an unknown copper (II) sulfate solution.

After completing the Preliminary Activity, you will first use reference sources to find out more about solutions, solution concentration, and Beer’s law investigations before you choose and investigate a researchable question utilizing Beer’s law technique.

Sensors and Equipment

This investigation features the following Vernier sensors and equipment.

Option 1

Option 2

Additional Requirements

You may also need an interface and software for data collection. What do I need for data collection?

Standards Correlations

See all standards correlations for Investigating Chemistry through Inquiry »

Investigation 11 from Investigating Chemistry through Inquiry Lab Book

<em>Investigating Chemistry through Inquiry</em> book cover

Included in the Lab Book

Vernier lab books include word-processing files of the student instructions, essential teacher information, suggested answers, sample data and graphs, and more.

Buy the Book

Go to top