Which are isotopes? An atom that has an atomic number of 35 and a mass number of 76 is an isotope of an atom that has
A)an atomic number of 31 and a mass number of 76.
B)an atomic number of 35 and a mass number of 80.
C)41 neutrons and 35 protons.
D)41 protons and 35 neutrons.

Question

Quizplus · Accepted Answer

Isotopes have the same number of protons but different numbers of neutrons. The atom mentioned in the question has an atomic number of 35, which means it has 35 protons. However, it has a mass number of 76, which means it has 41 neutrons. The only other option with an atomic number of 35 is (B), which has a different mass number of 80, indicating it is a different isotope of the same element. Option (A) has a different atomic number and the same mass number, making it a different element. Option (C) and (D) provide additional information about the composition of the atom but do not help to identify which other atom it is an isotope of.

Which Are Isotopes? an Atom That Has an Atomic Number