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Chemistry · Biology · Mathematics · Psychology. Built on the official 2028 syllabuses and real past papers.

Chemistry · 7.1.74 marksMarked in 7 s
3/ 4Nearly there
(a) Kc = [HI]² / ([H₂][I₂]) (b) H₂ = I₂ = 0.50 − 0.39 = 0.11 mol Kc = 0.78² / (0.11 × 0.11) = 50.3 units: mol⁻¹ dm³
✓
Correct Kc expression matched: Kc = [HI]² / ([H₂][I₂])
✓
Equilibrium moles 0.11 mol matched: 0.50 − 0.39 = 0.11
✓
Kc = 50.3 accept 50, 50.28
✕
No units The value is right, but Kc has no units here: the concentration terms cancel.

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