Question

What is the atomic number of 1 proton and 1 electron?

Answer 1

The atomic number of an element is defined by the number of protons in the nucleus of its atoms. Since you mentioned 1 proton, the atomic number is 1.

An atom with 1 proton and 1 electron corresponds to the element hydrogen (H). The electron does not affect the atomic number; it is simply the charge of the atom. Thus, the atomic number is 1.