Solutions and Mixtures

Graduate Fellow Kristina Pohaku Mitchell & Teacher Partner Sara Dozier

How do you tell the difference between a solution and a mixture? 

ABSTRACT

Solutions chemistry is abstract and confusing to many students. In this activity, students create their own working definition of a solution based on observations of familiar items. Small groups of students are presented with a variety of mixtures containing food, beverages and seasonings. In comparing and contrasting these homogeneous and heterogeneous mixtures, students use observable properties to create categories of materials.  After they have arrived at their own conclusions about homo- and heterogeneity, whole group instruction is used to formalize their ideas using academic language critical to their success in chemistry.

GRADE LEVEL: 9-12 

SUBJECT: Chemistry 

DURATION: 1- 90 minute period 

LEARNING OBJECTIVES: 

•       Students will be able to compare and contrast mixtures and solutions using several separation techniques and exploration of light scattering properties.

•       Students will be able to identify and execute separation methods on samples identified as mixtures using either filtration or centrifugation.