OSAT Chemistry case studies
OSAT Chemistry · Put your knowledge to work in context.
Chemistry (104) is the current Certification Examinations for Oklahoma Educators (CEOE) chemistry test, listed on the CEOE test menu alongside the other Oklahoma educator certification assessments. It replaced the retired Chemistry (004) version; the program page for (004) states plainly that the older test has retired and that the new Chemistry (104) test has replaced it and is now available. The OSAT Chemistry case studies are 5 cases and about 3,226 words.
1Acid Dilution and Spill Response in a Crowded Lab
During a 50-minute laboratory period, 26 students in four groups are preparing 1.8 L of 1.0 M sulfuric acid from 18 M stock. Each group receives 100 mL of the concentrated acid in a labeled beaker and a 2 L volumetric flask.
719 words, about 4 min2Percent Yield Above 100% in a Copper-Cycle Lab
Students perform a copper-cycle sequence starting with 2.00 g of copper wire. They dissolve the copper in nitric acid, precipitate copper(II) hydroxide with sodium hydroxide, heat it to form copper(II) oxide, dissolve the oxide in sulfuric acid, and reduce the copper ions back to metal with zinc.
684 words, about 3 min3Changing Color in a Cobalt Chloride Equilibrium
Five test tubes each contain 5.0 mL of 0.10 M CoCl2 in a water-ethanol solvent. The equilibrium is [Co(H2O)6]2+ (pink) + 4 Cl− ⇌ [CoCl4]2− (blue) + 6 H2O, and the forward reaction is endothermic.
635 words, about 3 min4Diagnosing Galvanic Cell Readings That Do Not Match the Nernst Equation
Four student groups build Zn-Cu galvanic cells. Each uses a zinc strip in ZnSO4 solution, a copper strip in CuSO4 solution, and a salt bridge of 1.0 M KNO3 in agar.
607 words, about 3 min5Choosing an Indicator for a Weak-Acid Titration
A teacher gives students 25.00 mL of an unknown weak monoprotic acid and 0.100 M NaOH. A pH titration curve shows the half-equivalence point at pH 4.80 and the equivalence point at 24.60 mL and pH 8.90.
581 words, about 3 min