MSCE Chemistry case studies

MSCE Chemistry · Put your knowledge to work in context.

The MSCE Chemistry credential is a specialty certification for chemists, laboratory scientists, quality-control analysts, and educators who need to demonstrate broad, working competence across the chemical sciences. It is intended for candidates who already hold a chemistry or related degree and want an independent, exam-based signal of their knowledge for employers, regulators, or professional development. The MSCE Chemistry case studies are 5 cases and about 3,758 words.

Phosphate Buffer pH Discrepancy Before an Enzyme Assay

You are preparing 1.00 L of 50.0 mM potassium phosphate buffer, pH 7.40, for an enzyme assay. The stock solutions are 0.200 M KH2PO4 (monobasic) and 0.200 M K2HPO4 (dibasic).

644 words, about 3 min 2

Rearrangement During HBr Conversion of a Hindered Secondary Alcohol

You need 2-bromo-3,3-dimethylbutane, a secondary bromide, as an intermediate. A colleague treats 10.0 g (97.9 mmol) of 3,3-dimethyl-2-butanol with 30 mL of 48% aqueous HBr and heats at reflux for 2 h.

690 words, about 3 min 3

Co(III) Complex with an Unexpected Magnetic Moment

You isolate a purple crystalline complex from the reaction of CoCl2·6H2O with excess ammonia and ammonium chloride, followed by oxidation with 30% H2O2 and acidification with HCl. The proposed formula is [Co(NH3)5Cl]Cl2 (M = 250.4 g/mol).

767 words, about 4 min 4

Headspace GC Method Fails Low-Level Ethanol QC

You are validating a headspace GC-FID method for residual ethanol in a solid excipient. The specification is ≤50 ppm.

781 words, about 4 min 5

Peroxide-Forming Solvents and Incompatible Waste During Lab Move

You are the chemical hygiene officer for a teaching lab moving buildings. In a fume hood you find: a 2.5 L amber bottle of diethyl ether labeled 'opened 2023-01-15'; a 500 mL bottle of THF with a faded label and no date; a 1 L glass bottle containing a yellow liquid labeled 'waste-DCM/acetone'; and a 250 mL bottle of 30% hydrogen peroxide stored beside a bottle of acetone.

876 words, about 4 min