What is indicated by the sum of protons and the neutrons?

Answer 1

By the sum of protons and neutrons we obtain the mass number of the atom which is written at the top of the atom periodic number. We can also obtain the mass number by adding the atomic number and the number of neutrons because the atomic number and the number of protons are same. You know that scientists have discovered some particles which are smaller than protons and neutrons and these are known as quartz.

Answer 2

Whether the element is an isotope in fairly good abundance or not is derived from the mass number in the nucleus (protons and neutrons). You can determine abundance from the Atomic Mass.

The mass of an electron is 9.11EE-31kg and is considered to be zero by a rounding assumption.

Answer 3

It will be atomic mass (if the weight of protons and neutrons are considered) or it will be mass number (if the number of protons and neutrons are considered).

Answer 4

Mass number = Number of protons + Number of neutrons

Answer 5

atomic mass