Question

What is an atoms atomic number and atomic mass when it has three P and 4 N?

Answer 1

The atomic number of an atom is determined by the number of protons it contains. In this case, since the atom has three protons (P), its atomic number is 3.

The atomic mass is the total number of protons and neutrons in the nucleus of the atom. Since this atom has 3 protons and 4 neutrons (N), you would add these together:

\[ \text{Atomic mass} = \text{Protons} + \text{Neutrons} = 3 + 4 = 7. \]

Thus, the atom has an atomic number of 3 and an atomic mass of 7. This corresponds to the element lithium (Li).