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O-LevelChemistryAtomic Structure5070/11 · May/June 2025 · Q51 Mark

A pure sample of element X has a relative atomic mass of 51.8. The sample consists of three isotopes. The table shows the relative masses and percentage abundances of two of the isotopes. What is the relative mass of the third isotope?

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A51
B52
C53
D54

✓ Correct answer

B: 52

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About this question

Topic
Atomic Structure, O-Level Chemistry (syllabus 5070). Multiple choice, 1 mark.
Source
O-Level Chemistry, May/June 2025 Paper 1 Variant 1, question 5.

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