Final answer:
The atomic number of an element is the number of protons in its nucleus. It is a characteristic that distinguishes different elements on the periodic table. The atomic number can be found by referring to the periodic table, and it determines the identity of the element.
Step-by-step explanation:
The atomic number (Z) of an element is the number of protons in the nucleus of each atom of that element. The atomic number is displayed above the elemental symbol in the periodic table, and it ranges from 1 to about 118. For example, hydrogen has an atomic number of 1, while helium has an atomic number of 2.
To find the atomic number of an element, you can refer to the periodic table. The atomic number is a whole number that indicates the number of protons an element has. It is important to note that the atomic number determines the element's identity and distinguishes it from other elements.
Therefore, when you are given the mass number and the atomic number of an element, you can find the number of neutrons by subtracting the atomic number from the mass number. Neutrons are particles found in the nucleus of an atom that have no charge, and their number can vary for different isotopes of the same element.