Question detail
Why do isotopes of the same element have different mass numbers? Use the proton number context to keep Mass number, atomic number and isotopes distinct from nearby atomic and nuclear radiation ideas.
Try the question, check the answer, then read the explanation to understand the curriculum point.
At a glance
MCQ
Type
practice
Style
Topic
Atoms and isotopes
Question
- A. They have different numbers of protons. (mass number atomic number and)
- B. They have different numbers of neutrons. (mass number atomic number and)
- C. They have different numbers of electrons. (mass number atomic number and)
- D. They have different atomic numbers. (mass number atomic number and)
Answer
The correct answer is They have different numbers of neutrons. (mass number atomic number and).
Explanation
The correct answer is They have different numbers of neutrons. (mass number atomic number and). It directly supports the learning objective: Explain why isotopes of the same element have the same chemical properties.. In Mass number, atomic number and isotopes, this is the best option because it matches the specific proton number context; the other options mix up nearby ideas such as activity, count rate, isotope notation, radiation type, or nuclear-equation changes.
Common mistake
Misconception about chemical properties of isotopes
Students often think that isotopes of the same element have different chemical properties because they contain different numbers of neutrons.
Explain that chemical properties are determined by the arrangement of electrons, which is the same for all isotopes of an element. Neutrons only affect the mass and nuclear stability, not the electron configuration or chemical behaviour.
Related flashcards
Flashcard 1 of 5
Related practice questions
Question 1 of 5
Choose an answer, get feedback, then move sideways through the set.