Learning objective
Calculate relative atomic mass from isotopic abundance data for mononuclear ions.
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At a glance
5
Flashcards
7
Questions
Topic
Atomic structure
Subtopic
Mass number, isotopes and mass spectrometry
Study support
Understand this objective
Short explanation
Calculate relative atomic mass from isotopic abundance data for mononuclear ions. sits within Mass number, isotopes and mass spectrometry for Atomic structure in AQA A-Level Chemistry 7405. A strong exam response should identify the relevant chemical relationship, choose the correct formula or representation where needed, substitute values or evidence carefully, and state the final conclusion with appropriate units or terminology. When revising this objective, focus on the distinction between the concept being tested and neighbouring ideas so that calculation steps, organic representations, or equilibrium reasoning do not collapse into a generic answer.
Key concepts
Why it matters
This objective helps connect Mass number, isotopes and mass spectrometry to exam-style questions, flashcards, and revision notes for Atomic structure.
Common mistakes
1 linked- Common Mistake in Relative Atomic Mass Calculation: To correctly calculate relative atomic mass, use the formula: relative atomic mass = (isotope mass x abundance) / 100. For example, if you have an isotope of mass 10 with an abundance of 80% and another of mass 11 with an abundance of 20%, the calculation would be: (10 x 80) + (11 x 20) = 800 + 220 = 1020. Then divide by 100 to get 10.2. Therefore, the relative atomic mass is 10.2.
Revision tools
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Flashcards5 linked cards
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Practice Questions7 linked questions
Question 1 of 7
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Revision notestopic notes
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Open revision notesRelated learning objectives
- Explain that scientific understanding of atomic structure has developed over time.
Fundamental particles
- State the relative charge and relative mass of protons, neutrons and electrons.
Fundamental particles
- Describe an atom as a nucleus containing protons and neutrons surrounded by electrons.
Fundamental particles
- Use particle properties to compare atoms, ions and isotopes.
Fundamental particles
- Determine the numbers of protons, neutrons and electrons in atoms and ions from mass number, atomic number and charge.
Mass number, isotopes and mass spectrometry