Question

What is the mass number of an atom that has 12 protons, 13 neutrons, and 13 electrons?
tts Icon

13
tts Icon

25
tts Icon

12
tts Icon

26

Answer 1

The mass number of an atom is calculated by adding the number of protons and neutrons together.

In this case, the atom has:
- 12 protons
- 13 neutrons

So, the mass number = 12 (protons) + 13 (neutrons) = 25.

The correct answer is **25**.