A-LevelChemistryEquilibria9701/12 · Oct/Nov 2009 · Q81 Mark

PCl5 dissociates as follows. PCl5(g) → PCl3(g) + Cl2(g) The extent of dissociation is 13% at 160°C and 100% at 300°C. Which pair of statements about this formation of PCl3 is correct? [Figure 8.1]

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Ashape of PCl3 molecule: pyramidal, the reaction is: endothermic

Bshape of PCl3 molecule: pyramidal, the reaction is: exothermic

Cshape of PCl3 molecule: trigonal, the reaction is: endothermic

Dshape of PCl3 molecule: trigonal, the reaction is: exothermic

✓ Correct answer

A: shape of PCl3 molecule: pyramidal, the reaction is: endothermic

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Topic: Equilibria, A-Level Chemistry (syllabus 9701). Multiple choice, 1 mark.
Source: A-Level Chemistry, Oct/Nov 2009 Paper 1 Variant 2, question 8.

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