BSEH SS Chemistry case studies
BSEH SS Chemistry · Put your knowledge to work in context.
BSEH Senior Secondary Chemistry is the Class XII chemistry paper set by the Board of School Education, Haryana for candidates completing the senior secondary stage at affiliated schools. It is taken mainly by science-stream students - medical and non-medical - who need the subject for the school-leaving certificate, for university admission, and for eligibility in professional entrance examinations. The BSEH SS Chemistry case studies are 5 cases and about 3,899 words.
1Nickel plating line misses a thickness audit after a rack fault
A job-shop plating line coats steel brackets with nickel from a Watts bath (NiSO4·6H2O, NiCl2, boric acid, pH 4.0, 50 °C). Production runs 12 brackets per rack, each bracket exposing 0.0045 m² of surface.
824 words, about 4 min2First-order hydrolysis: can the oral solution reach a 24-month shelf life?
A pharmaceutical team is developing a 50 mg mL⁻¹ oral solution of a drug that hydrolyses by first-order kinetics. An accelerated study at 60 °C gives 92.0% of the label claim remaining after 30 days.
752 words, about 4 min3Distinguishing cis and trans bis(ethylenediamine)dichlorocobalt(III) salts
A student prepares two samples of the complex [Co(en)2Cl2]Cl, where en = ethane-1,2-diamine, by two different routes. Sample A is optically inactive, has a dipole moment of approximately zero in a non-aqueous solvent, and shows no change in optical rotation on standing.
758 words, about 4 min4Switching a water plant from chlorine to chlorine dioxide under a THM limit
A water utility treats 20,000 m³ day⁻¹ and must reduce trihalomethanes (THMs). The current chlorine gas dose is 1.5 mg L⁻¹ as Cl2 equivalent.
757 words, about 4 min5Separating benzoic acid, benzaldehyde and benzyl alcohol without chromatography
A 12.0 g laboratory mixture contains benzoic acid, benzaldehyde and benzyl alcohol. The mixture must be separated into three recovered compounds, each at ≥80% recovery, using only a separatory funnel, a rotary evaporator, a steam bath and the following reagents: saturated NaHCO3, 1 M NaOH, saturated NaHSO3, diethyl ether, anhydrous Na2SO4 and dilute HCl.
808 words, about 4 min