Difficulty: Medium
Average Score: 89%
Entry Exam
What does the term 'atomic number' represent?
Correct answer
B
Rationale
The atomic number represents the number of protons in the nucleus of an atom. This number uniquely identifies an element and determines its placement in the periodic table. The number of neutrons and electrons can vary among different isotopes of an element, but the number of protons remains constant, defining the element's atomic number. Therefore, the correct answer is the number of protons (Choice B).