Question

In the nucleus of an atom, there are 18 protons and 20 neutrons. What are the atomic number and mass number of this isotope?

Answer 1

Atomic number is 18. Mass number is 38.

Step-by-step explanation:

Atomic number is the number of protons in the nucleus of an atom. It is represented with letter Z. So, for the given question atomic number is 18.

Mass number is the total number of neutrons and protons in the nucleus of an atom. It is represented with letter A.

So, for the given problem:

A=Z+neutrons

A=18+20

A=38

Answer 2

atomic number is 18 and mass number is 38.