Question

A neutral atom of sodium has $11$ protons. How do you use this information to explain the total number of electrons that are in a sodium atom?

Answer 1

A neutral atom contains the same number of positively and negatively charged species. If any of the values change, the atom becomes an ion. Atoms can accept or release electrons to form ions.

Complete step by step answer: An atom contains positively charged, negatively charged and neutral species. The positively charged species in an atom is proton. The negatively charged species in an atom is electron. The neutral species in an atom is neutron. Neutrons and protons are found inside the nucleus and electrons are found outside the nucleus, orbiting the nucleus through specified paths called shells. In order to become an atom neutral, the number of positively charged and negatively charged species in the atom should be the same. i.e. the number of protons and electrons should be the same in a neutral atom. It is given that sodium contains $11$ protons and the atom is neutral. Therefore, the sodium will contain $11$ electrons in order to maintain neutrality.
Hence the total number of electrons present in a sodium atom is $11$ .

Additional information-
Atomic number of an atom is the number of protons present inside the nucleus of the atom. Hence the atomic number of sodium atoms is $11$ .

Note:
When an atom loses an electron it becomes a positively charged ion. In the same way, on gaining an electron an atom becomes negatively charged ion. Properties of ions are different from that of neutral atoms.