Question

Mark the correct statement.

• A. Nuclei of different elements can have the same number of neutrons
• B. Every element has only two stable isotopes
• C. Only one isotope of each element is stable
• D. All isotopes of every element are radioactive

Answer 1

Answer: (A)

Nuclei of different elements can have the same number of neutrons

Answer 2

Nuclei of different elements having the same mass number are called isotones e.g., $4 ⥂ Be^{9}$and $5B^{10}$.