Video Transcript
Which of the following is displayed in a Lewis dot diagram? (A) The valence protons in an element. (B) The neutrons, protons, and electrons in an element. (C) The valence electrons in an element. (D) The electrons in the last two shells in an element. (E) All the electrons in an element.
Lewis dot diagrams, also called Lewis structures or Lewis structure diagrams, are simple schematic illustrations. Lewis structures feature the atomic symbol for an element, in this case hydrogen, which is surrounded by dots. Each dot in a Lewis dot diagram represents a valence electron. Atoms of hydrogen have one valence electron. So the Lewis structure for hydrogen has one dot. Atoms of oxygen have six valence electrons, so the Lewis structure has six dots. Oxygen also has two core electrons. These core electrons, as well as the nucleus, are represented by the atomic symbol.
We can also create Lewis dot diagrams for molecules. For example, we could create a Lewis structure for a water molecule. In a water molecule, the hydrogen and oxygen atoms are joined by a chemical bond. Each atom participating in the bond donates one of their valence electrons to form the bond. This type of chemical bond formed by the sharing of valence electrons is called a covalent bond. We could represent the covalent bond in our Lewis structure for the water molecule using two dots or by drawing a line between the two atoms. So, as we’ve seen, Lewis dot diagrams or Lewis structures display the valence electrons in an element. So answer choice (C), the valence electrons in an element, is the correct answer.
