Potassium’s atomic number is 19, and its atomic mass is approximately 39. How many neutrons does potassium have?(2 points)

Question

Responses

19
19

58
58

39
39

20

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:

• Atomic mass ≈ 39
• Atomic number = 19

So,

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

The correct response is 20.