Samantha Glazier, Saint Lawrence University
Nadia Marano, Saint Lawrence University
Laura Eisen, The George Washington University
All general chemistry courses teach about solubility but students often have misconceptions about why some substances are soluble and some not. The purpose of this workshop is to provide several inquiry-based activities for teachers of first year college chemistry and advanced high school chemistry to help students explore the factors affecting solubility and avoid misconceptions about the role of energy. The activities introduce energy changes in molecular and ionic dissolution in water, emphasizing that compounds can dissolve exothermically or endothermically. We qualitatively introduce the idea of entropy (molecular reorganization) as an important contributor to whether or not a compound can dissolve. Next, we use mixtures of different salts to determine which ionic compounds are insoluble and develop a simple solubility rule based on ionic charges. We use data of lattice and hydration energies to model the solution process and to discuss the physical basis for simple solubility rules. Finally, we look at the reasons for exceptions to simple solubility rules. Time permitting, we explore applications of these ideas to topics such as vitamins, barium X-rays and protein folding. The workshop will model inquiry-based learning by having participants complete the activities and then discuss them; 3-hour session.
Intended Audience: HS(AP)/UG
$15 fee; limit of 30 participants
Monday, July 30, 9:30 a.m. – 12:30 p.m., 151 N Frear