The atomic mass of an element cannot be determined solely from its atomic number. The atomic number (also known as the Z number) represents the number of protons in the nucleus of an atom, which uniquely identifies the element.
The atomic mass of an element takes into account both the protons and neutrons in the nucleus. Since different isotopes of an element can have varying numbers of neutrons, the atomic mass is an average of the masses of all naturally occurring isotopes of that element, weighted by their abundance.
To determine the atomic mass of an element, you would typically refer to the periodic table. The atomic mass of an element is usually listed below the element's symbol. It represents the average atomic mass of all isotopes of that element found in nature. This value is often a decimal number because it takes into account the isotopic abundances.
Therefore, if only the atomic number of an element is given, you would need to refer to the periodic table or other reliable sources to find the corresponding atomic mass of that element.