Potassium’s atomic number is 19, and its atomic mass is approximately 39. How many neutrons does potassium have?(1 point)
Responses
58
58
19
19
20
20
39
The number of neutrons in an atom can be determined by subtracting the atomic number (the number of protons) from the atomic mass number (the sum of the number of protons and neutrons).
For potassium:
- Atomic number (number of protons): 19
- Atomic mass (approximate, typically closest to the mass number of its most stable or most common isotope): 39
To find the number of neutrons:
Number of neutrons = Atomic mass - Atomic number
Number of neutrons = 39 - 19
Number of neutrons = 20
Therefore, potassium has approximately 20 neutrons.