Potassium’s atomic number is 19, and its atomic mass is approximately 39. How many neutrons does potassium have?(1 point)

Question

Responses

19
19

20
20

58
58

39

Answer 1

To find the number of neutrons in an atom, you can use the formula:

\[ \text{Number of Neutrons} = \text{Atomic Mass} - \text{Atomic Number} \]

For potassium (K):

• Atomic number = 19
• Atomic mass (approximately) = 39

So, the calculation would be:

\[ \text{Number of Neutrons} = 39 - 19 = 20 \]

Therefore, potassium has 20 neutrons. The correct response is:

20