Different isotopes of an element are atoms of that element which have
A)the same atomic number and the same mass number.
B)the same atomic number and different mass number.
C)different atomic number and the same mass number.
D)different atomic number and different mass number.

Question

Quizplus · Accepted Answer

Isotopes are atoms of the same element with different numbers of neutrons, which means they have the same atomic number (since it is determined by the number of protons in the nucleus) but different mass numbers (since the mass number is determined by the total number of protons and neutrons in the nucleus). Therefore, option B (same atomic number but different mass number) is correct.

Different Isotopes of an Element Are Atoms of That Element