O-LevelChemistryAtomic Structure5070/12 · May/June 2019 · Q51 Mark

Two particles, K⁺ and Ar, can be written as ³⁹₁⁹K⁺ and ⁴⁰₁⁸Ar. Which statement about these particles is correct?

AAr has more neutrons than K⁺.

BK has more nucleons than Ar.

CK⁺ has 20 electrons.

DK⁺ has a greater mass than Ar.

✓ Correct answer

A: Ar has more neutrons than K⁺.

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Topic: Atomic Structure, O-Level Chemistry (syllabus 5070). Multiple choice, 1 mark.
Source: O-Level Chemistry, May/June 2019 Paper 1 Variant 2, question 5.

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