The atomic mass of an element whose atoms consist of six protons, seven neutrons, and six electrons is 6 12 13 19

Given the formula for neutrons = atomic mass - atomic number/protons/ electrons (assuming it is a neutral atom).
atomic mass = neutrons + atomic number/protons/ electrons
atomic mass = 7 + 6
atomic mass = 13

The atomic mass of this element is therefore 13 amu.

Where is the following?

Answer( precipitate );