A-LevelChemistryGroup 17Oct/Nov 2015Paper 1 Q171 Mark
A student observed the reactions when sodium chloride and sodium iodide were each reacted separately with concentrated sulfuric acid and with concentrated phosphoric acid. Some observations are recorded in the table. sodium chloride with conc. H2SO4: colourless acidic gas formed sodium chloride with conc. H3PO4: colourless acidic gas formed sodium iodide with conc. H2SO4: purple vapour formed sodium iodide with conc. H3PO4: colourless acidic gas formed Which deduction can be made from these observations?
AConcentrated phosphoric acid is a stronger oxidising agent than concentrated sulfuric acid.
BConcentrated phosphoric acid is a stronger oxidising agent than iodine.
CConcentrated sulfuric acid is a stronger oxidising agent than chlorine.
DConcentrated sulfuric acid is a stronger oxidising agent than iodine.
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The correct answer is D. This question tests the candidate's understanding of group 17 within the Chemistrysyllabus. The examiner's mark scheme requires...
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