Potassium’s atomic number is 19, and its atomic mass is approximately 39. How many neutrons does potassium have?(1 point)
Responses
20
39
19
58
The atomic number of an element represents the number of protons in its nucleus. Therefore, potassium has 19 protons. The atomic mass of an element represents the sum of its protons and neutrons. Since the atomic mass of potassium is 39 and it has 19 protons, the number of neutrons in potassium would be 39 - 19 = 20.
So, the correct answer is 20.