Algonquin College Health Program Assessment (AC-HPAT) Practice Exam

An atom with an atomic number of 58 and an atomic mass of 118 has how many neutrons?

1. 60

2. 58

3. 118

4. 50

The correct answer is: 60

To determine the number of neutrons in an atom, you can use the formula: Number of Neutrons = Atomic Mass - Atomic Number. In this case, the atom has an atomic number of 58 and an atomic mass of 118. Substituting these values into the formula gives: Number of Neutrons = 118 - 58 = 60. This means the atom contains 60 neutrons. Understanding this calculation is important, as the atomic number represents the number of protons in the nucleus, while the atomic mass is the total number of protons and neutrons combined. Therefore, this knowledge is crucial for grasping the structure of atoms in chemistry and physics.