LC Chemistry case studies
LC Chemistry · Put your knowledge to work in context.
Leaving Certificate Chemistry is the Irish senior-cycle subject examined by the State Examinations Commission and commonly taken over two years, with Higher and Ordinary level papers. It suits students who want a laboratory-based science qualification for university entry in science, medicine, pharmacy, engineering or education, and it also stands alone as a grounding in chemical reasoning. The LC Chemistry case studies are 5 cases and about 3,283 words.
1Reading a Periodic Table Pattern from Ionisation Energies
A student is analysing a data sheet for an element Q. The successive ionisation energies of Q, in kJ mol⁻¹, are: 1st 578; 2nd 1817; 3rd 2745; 4th 11578; 5th 14831; 6th 18378.
706 words, about 4 min2Vinegar Titration: Choosing Titres and Explaining an Overestimate
A student is determining the ethanoic acid content of a commercial vinegar. She pipettes 25.0 cm³ of the vinegar into a 250.0 cm³ volumetric flask and makes it up to the mark with distilled water.
675 words, about 3 min3Spirit-Burner Calorimetry: When the Data Book Is Not Wrong
A student burns ethanol from a spirit burner beneath a copper calorimeter containing 200.0 g of water. The burner weighs 185.42 g before the experiment and 183.96 g afterwards.
656 words, about 3 min4Identifying an Unknown Liquid: Which Test Is Decisive
An unknown colourless liquid Z is issued for identification. It boils at 78 °C, mixes completely with water, and gives a neutral result on moist pH paper.
585 words, about 3 min5Copper Plating: A Mass Gain Above 100% Efficiency
A student electroplates copper onto a brass key using copper electrodes and copper(II) sulfate solution. The key is weighed at 4.86 g, immersed as the cathode, and a current of 0.50 A is passed for 32.0 minutes (1920 s, so 960 C).
661 words, about 3 min