Question

what element has 81 protons in the nuclei of its atom?

Answer 1

Thallium

Answer 2

The answer is Thallium because the ATOMIC NUMBER is what you need to look at to find out how many protons are in an element. In the attached drawing, the atomic number is 81, meaning Thallium has 81 protons. Below is TI, which stands for Thallium and the last number below is the atomic mass. So if you want to find out which element has whatever amount of protons in its atom, you can just look at the top number, the atomic number.