Question

Isotopes are the atoms of the same element, with the same atomic number, but with different:

• A. Atomic number
• B. Mass number
• C. Number of electrons
• D. Chemical nature

Hint:

Isotopes have the same chemical properties but different physical properties due to differences in mass.

Answer 1

The Correct Option is B

• Option 1: Atomic number - This is incorrect. Isotopes have the same atomic number, as they are atoms of the same element. The atomic number refers to the number of protons, which remains the same in isotopes. 
• Option 2: Mass number - This is the correct answer. Isotopes of the same element have the same atomic number but different mass numbers, as they contain different numbers of neutrons.
• Option 3: Number of electrons - This is incorrect. The number of electrons in isotopes remains the same if the atoms are neutral. The number of electrons does not affect the classification of isotopes.
• Option 4: Chemical nature - This is incorrect. Isotopes of the same element have the same chemical nature because they have the same number of electrons and the same atomic structure.

Explanation:

Isotopes are atoms of the same element that have the same atomic number (same number of protons) but different mass numbers. This difference in mass number occurs due to varying numbers of neutrons in the nucleus, which gives isotopes of an element different atomic masses but identical chemical properties.