Question

How many electrons does a neutral potassium atom have? How many protons? How many electrons does a neutral fluorine atom have? What happens in the molecule of potassium fluoride?

Answer 1

An element's atomic number is the same as the number of protons in the element. Because potassium has an atomic number of 19, it has 19 protons.

A neutral atom has the same number of protons and electrons, so one neutral atom of potassium must also have 19 electrons.

Fluorine has atomic number 9. Atomic number is the number of protons present in the nucleus of an atom. In every stable (Neutral) atom the number of electrons are equal to the number of protons. Therefore, the number of electrons in an atom of fluorine are 9.