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Model Paper 4 — Science STD 9 — Question

Gujarat BoardEnglish MediumSTD 9ScienceModel Paper 41 Mark
MCQ
Assertion (A): Isotopes are electrically neutral.
Reason (R): Isotopes are species with same mass number but different atomic numbers.
  • A
    Both A and R are true and R is the correct explanation of A
  • B
    Both A and R are true but R is not the correct explanation of A
  • ✓
    A is true but R is false.
  • D
    A is false but R is true.
✓

Answer

Correct option: C.
A is true but R is false.
(c)A is true but R is false.
Explanation: Isotopes are species with same atomic number but different mass numbers.

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