Question

Which of the following statements is INCORRECT?

Options

• All isotopes of hydrogen contain one proton and one electron but different number of neutrons in the nucleus.

• Tritium is a radioactive nuclide.

• The most abundant isotope of hydrogen is protium.

• Isotopes of an element have the same atomic mass number but different atomic numbers.

Answer 1

Isotopes of an element have the same atomic mass number but different atomic numbers.

Explanation:

Because their nuclei have varying quantities of neutrons, isotopes of the same element have the same atomic number (number of protons) but different atomic mass values.