Maharashtra HSC Chemistry case studies
Maharashtra HSC Chemistry · Put your knowledge to work in context.
The Maharashtra HSC Chemistry examination is the Class 12 chemistry paper set by the Maharashtra State Board of Secondary and Higher Secondary Education (MSBSHSE). It is taken by students completing higher secondary schooling in the science stream, and its marks are used for college admission, particularly for BSc, pharmacy, engineering and medical pathways where chemistry is a required subject. The Maharashtra HSC Chemistry case studies are 5 cases and about 3,161 words.
1Refractory MgO and Non-stoichiometric TiO
A ceramic plant supplies magnesium oxide powder for refractory bricks. X-ray diffraction shows a face-centred cubic NaCl-type lattice with edge length a = 4.21 Å and four formula units per unit cell (M(MgO) = 40.30 g mol⁻¹).
621 words, about 3 min2Normal Saline Batch Failure and Paediatric Isotonic Solution
A 600-bed hospital pharmacy prepares 1 L batches of 0.90% w/v sodium chloride (M = 58.44 g mol⁻¹) using a Class A volumetric flask and a balance readable to 0.001 g. The specification is 290 mOsm kg⁻¹, but the in-house freezing-point osmometer reads 255 mOsm kg⁻¹ for the latest batch.
674 words, about 3 min3Buffer Choice for a Calcium-containing Enzyme Assay
A molecular-biology laboratory needs 1.0 L of 0.10 M buffer at pH 7.40 for an enzyme assay that also contains 1.0 mM CaCl2 and 1.0 mM MgCl2. Available stock solutions, each 0.10 M, are sodium acetate (pKa 4.76), NaH2PO4/Na2HPO4 (pKa2 7.20), Tris base/Tris-HCl (pKa 8.06) and NH4Cl/NH3 (pKa 9.25).
632 words, about 3 min4Arrhenius Extrapolation for an Ester Prodrug
A formulation scientist is reviewing stability data for an ester prodrug in pH 7.4 phosphate buffer. At 50.0 °C, a 0.200 M solution falls to 0.100 M in 40.0 days, and a separate 0.100 M solution falls to 0.050 M in 40.0 days.
577 words, about 3 min5Werner Complexes and Nickel(II) Geometry
A student prepares cobalt ammine complexes from CoCl2·6H2O and ammonia in air, and two nickel complexes. Sample A analyses as CoCl3·5NH3 (M = 250.4 g mol⁻¹); 0.150 g of A treated with excess AgNO3 gives 0.172 g AgCl (M = 143.3 g mol⁻¹), and A has a magnetic moment of 0.0 BM.
657 words, about 3 min