[Chemistry] How do you pronounce that?

Good day,

I still need a little help understanding how to pronounce the following. I'm really looking forward to your helpful answers.

Take "tritium," or "superheavy hydrogen," as an example. It has one proton and two neutrons. It is unstable and therefore radioactive. Symbol: T.

Mass number (atomic mass in u): 3

Atomic number (number of protons): 1

Neutron number = mass number – atomic number (proton number) = 3 – 1 = 2

• But how do you pronounce what is shown in the picture?
• What is the name given to this representation used in the picture?