Knowledge and Skills Statement
Science concepts. The student understands and can apply the factors that influence the behavior of solutions.
Further Explanation
Concentration can be expressed in multiple ways, such as molarity, parts per million, or percent. It is helpful to consider how the concentration of a solution affects its use. The concentration of a solution affects the speed of particle collision within the solution. The more concentrated a solution is, the more particles of solute there are, and the more collisions there will be in a unit of time. A less concentrated solution will have fewer collisions because the particles are farther apart. Knowing the concentrations of the solutions involved helps determine the rate of dissolution of a substance (such as in cleaning) or the rate of a particular reaction.
Supporting Information
Research
Wakeley, Dawn M., and Hans de Grys. "Developing an Intuitive Approach to Moles. Journal of Chemical Education 77, no. 8 (2000):1007-1009. https://doi.org/10.1021/ed077p1007
Summary: The concept of the mole is one of fundamental ideas in basic chemistry and is a powerful tool for determining chemical amounts. By developing an intuitive approach to understanding moles and using the foundation to further develop the ideas of molar conversions and stoichemistry, students are encouraged to practice critical thinking skills and to apply their understanding in the classroom and in the laboratory.
Research
Mojica, Elmer-Rico E. and Rita K. Upmacis. (2022). "Challenges Encountered and Students' Reactions to Practices Utilized in a General Chemistry Laboratory Course During the COVID-19 Pandemic." Journal of Chemical Education 99, no.2 (2022):1053. https://doi.org/10.1021/acs.jchemed.1c00838
Summary: We evaluated the use of (i) videos of lab demonstrations, (ii) Microsoft PowerPoint slides with voice-over recordings that were prepared to guide students further in the particular procedure of the experiment, and (iii) kitchen-based experiments that students could perform at home for our General Chemistry I laboratory course. It was found that the videos were beneficial and the kitchen-based experiments allowed students to experience performing hands-on experiments and helped them observe and relate to concepts (such as classifying matter, making physical measurements, employing units and significant figures, preparing solutions, calculating moles and molarity, and employing separation techniques) that were discussed in the lecture portion of the course.