Question

An atom with 19 protons and 18 neutrons is a(n)

A. Isotope of potassium(K)
B. Standard atom of argon(Ar)
C. Standard atom of (K)
D. Isotope of argon (Ar)

Answer 1

Answer: A. Isotope of potassium(K)

Explanation: Founders Educere answer.

Answer 2

A

Step-by-step explanation:

The number of protons indicates the element so we know it's potassium. To get the number of neutrons you subtract the number of protons (19) from the mass number which for potassium is 39.

39-19=20 neutrons

Because you have 18 neutrons then yours would be an isotope.