Lecture Connections: Absorbance of UV Light by Sunscreens
| Keyword | General Concept | Explanation |
| Solutions | classifying matter | a homogeneous mixture, a physical mixture of uniform composition; |
| mixtures | classifying matter | Two or more substances that are physically rather than chemically combined. A mixture can be separated through physical means (ex. filtering, dissolving in water, etc.) |
| Beer's Law Plot | concentration, molarity, solutions | A mathematical relationshipthat depicts the relationship between concentration of a solution and its absorbance at a given wavelength; data plotted as a graph |
| Dilution | Stoichiometry | The process of making a less concentrated solution from a more concentrated one by adding a known quantity of solvent. |
| solute, solvent | properties of matter | A solvent dissolves a solute. In this lab, isopropyl alcohol is the solvent; sunscreen is the solute. |
| Electron structure | electron structure, electromagnetic spectrum | The movement of electrons from one energy level to some higher energy level after absorbing and releasing energy (light) |
| spectrum (pl. spectra) | electromagnetic spectrum; absorbance spectrum |
a UV-vis spectrum is produced by electrons absorbing and releasing energy at a particular wavelength and absorbance; In this lab, the spectra occur in the UV region of the spectrum |
Articles from the Journal of Chemical Education: (PDF Reader Required)