UAE TLS Chemistry Test case studies
UAE TLS Chemistry Test · Put your knowledge to work in context.
The UAE Teacher Licensing System (TLS) Chemistry Test is a subject-matter examination used within the Emirates' teacher licensure process for candidates who teach chemistry. It is intended for practising and prospective chemistry teachers in public and private schools, and for graduates seeking to enter the profession, who must demonstrate that their disciplinary knowledge meets the standard expected of a classroom teacher. The test is not a test of pedagogy alone; it samples the full undergraduate chemistry curriculum and asks you to explain, calculate and predict, not merely recall. Expect items across atomic structure and bonding, the mole and stoichiometry, gases and kinetic theory, thermochemistry, kinetics and equilibrium, acids and bases, redox and electrochemistry, organic functional groups and reaction types, and practical laboratory and analysis skills. The UAE TLS Chemistry Test case studies are 5 cases and about 1,898 words.
1The Sealed Vessel and the Shifting Equilibrium
A 2.0 L rigid steel vessel at 700 K is charged with 0.40 mol H2, 0.40 mol I2, and 1.20 mol HI. The reaction H2(g) + I2(g) ⇌ 2 HI(g) has Kc = 54.3 at 700 K.
380 words, about 2 min2The Discrepant Titration of a Cleaning Acid
A student standardises a batch of hydrochloric acid cleaner by titrating 25.00 mL aliquots against 0.1000 M NaOH using phenolphthalein. Three titres are 24.10 mL, 24.15 mL, and 28.90 mL.
368 words, about 2 min3Choosing an Electrode for a Corroding Pipeline
A buried mild-steel pipeline is protected by a sacrificial anode. Two candidate anodes are proposed: zinc (E° Zn²⁺/Zn = −0.76 V) and magnesium (E° Mg²⁺/Mg = −2.37 V).
377 words, about 2 min4The Warm Flask That Would Not Cool
A student dissolves 8.00 g of ammonium nitrate (molar mass 80.0 g/mol) in 100.0 g of water in a polystyrene cup calorimeter. The temperature falls from 22.4 °C to 16.9 °C.
360 words, about 2 min5Identifying an Unknown Carbonyl Compound
An unknown liquid (boiling range 78–80 °C) is submitted for identification. Tests: it gives an orange precipitate with 2,4-dinitrophenylhydrazine (2,4-DNP); it does not give a silver mirror with Tollens' reagent; it gives a yellow precipitate with alkaline iodine (iodoform) test.
413 words, about 2 min