OAE Chemistry case studies
OAE Chemistry · Put your knowledge to work in context.
The OAE Chemistry exam is one of the Ohio Assessments for Educators subject-matter tests used by the Ohio Department of Education and Workforce for educator licensure. It is typically taken by candidates seeking an initial teaching license in chemistry, or by currently licensed teachers adding a chemistry endorsement. The OAE Chemistry case studies are 5 cases and about 3,326 words.
1The 'Alkaline Water' Seed Germination Trial
A high school chemistry teacher is mentoring a student's science fair project on whether alkaline water improves radish seed germination. The student prepared three treatments: tap water at pH 7.2, bottled alkaline water at pH 8.9, and tap water adjusted to pH 8.9 with NaOH.
551 words, about 3 min2Identifying an Unknown Liquid with Lewis Structures and IMFs
An advanced chemistry class is identifying an unknown colorless liquid. The teacher provides the following data: the liquid is miscible with water, has a sharp odor, boils at about 118 degrees Celsius, has a molar mass near 60 grams per mole, and its 0.10 M aqueous solution has a pH of 2.9 and conducts electricity weakly.
700 words, about 4 min3The Over-100% Yield Precipitate
During a stoichiometry lab, students mix 25.0 mL of 0.200 M calcium chloride with 25.0 mL of 0.200 M sodium carbonate and collect the calcium carbonate precipitate by vacuum filtration. The teacher tells them to dry the precipitate to constant mass.
708 words, about 4 min4The Magnesium-HCl Rate Study with a Confounded Trial
Students study the reaction of magnesium ribbon with hydrochloric acid by timing how long a 5.0 cm strip takes to disappear. They run four trials at room temperature unless noted: 0.50 M HCl, 95 s; 1.0 M HCl, 48 s; 1.5 M HCl, 18 s, but the water bath for that trial was 35 degrees Celsius because another class had used the room-temperature bath; 2.0 M HCl, 30 s, but the magnesium strip was only 3.0 cm because the supply ran low.
692 words, about 3 min5Titration of a Weak Acid with a Late Endpoint
A student titrates 25.0 mL of an unknown weak monoprotic acid with 0.100 M sodium hydroxide. The burette reads 0.50 mL initially.
675 words, about 3 min