Describe the differences between atomic number and atomic mass.

Atomic number is the number of protons in an atom's nucleus, while atomic mass is the total number of protons and neutrons.

The atomic number of an element is unique to that element and determines its position on the periodic table. It is equal to the number of protons in the nucleus of an atom of that element. For example, carbon has an atomic number of 6, meaning it has 6 protons in its nucleus.

Atomic mass, on the other hand, is the total number of protons and neutrons in an atom's nucleus. It is measured in atomic mass units (amu) and is often listed as a decimal on the periodic table. For example, carbon has an atomic mass of approximately 12 amu, which is the sum of its 6 protons and 6 neutrons.

The difference between atomic number and atomic mass is important because it helps distinguish between isotopes of an element. Isotopes are atoms of the same element that have different numbers of neutrons, and therefore different atomic masses. For example, carbon-12 and carbon-14 are both isotopes of carbon, but carbon-12 has an atomic mass of 12 amu (6 protons and 6 neutrons) while carbon-14 has an atomic mass of 14 amu (6 protons and 8 neutrons).

In summary, atomic number and atomic mass are both important properties of an atom, but they represent different aspects of the atom's composition. Atomic number is the number of protons, while atomic mass is the total number of protons and neutrons.