https://www.khanacademy.org/science/ap-chemistry-beta/x2eef969c74e0d802:molecular-and-ionic-compound-structure-and-properties/x2eef969c74e0d802:lewis-diagrams/v/drawing-lewis-diagrams 2022-09-07T08:21:01.673602243Z Drawing Lewis diagrams A Lewis diagram shows how the valence electrons are distributed around the atoms in a molecule. Shared pairs of electrons are drawn as lines between atoms, while lone pairs of electrons are drawn as dots next to atoms. When constructing a Lewis diagram, keep in mind the octet rule, which refers to the tendency of atoms to gain, lose, or share electrons until they are surrounded by eight valence electrons (an octet). Sal Khan video https://cdn.kastatic.org/ka_thumbnails_cache/70da601e-6fd0-45f2-8dcf-865ecb21e47e_1280_720_base.png Drawing Lewis diagrams A Lewis diagram shows how the valence electrons are distributed around the atoms in a molecule. Shared pairs of electrons are drawn as lines between atoms, while lone pairs of electrons are drawn as dots next to atoms. When constructing a Lewis diagram, keep in mind the octet rule, which refers to the tendency of atoms to gain, lose, or share electrons until they are surrounded by eight valence electrons (an octet). https://cdn.kastatic.org/ka-youtube-converted/9BZFphoY-vo.mp4/9BZFphoY-vo.mp4 428 Octet rule https://www.khanacademy.org/science/ap-chemistry-beta/x2eef969c74e0d802:molecular-and-ionic-compound-structure-and-properties/x2eef969c74e0d802:lewis-diagrams/v/exceptions-to-the-octet-rule 2022-09-07T08:21:01.673602243Z Exceptions to the octet rule While most atoms obey the duet and octet rules, there are some exceptions. For example, elements such as boron or beryllium often form compounds in which the central atom is surrounded by fewer than eight electrons (e.g., BF₃ or BeH₂). In contrast, many elements in the third-row and beyond have been observed to exceed the octet rule, forming compounds in which the central atom is surrounded by more than eight electrons (e.g. ICl₄⁻ or PF₅). Sal Khan video https://cdn.kastatic.org/ka_thumbnails_cache/d12c78ae-4718-4fae-9cfe-d5fff448d594_1280_720_base.png Exceptions to the octet rule While most atoms obey the duet and octet rules, there are some exceptions. For example, elements such as boron or beryllium often form compounds in which the central atom is surrounded by fewer than eight electrons (e.g., BF₃ or BeH₂). In contrast, many elements in the third-row and beyond have been observed to exceed the octet rule, forming compounds in which the central atom is surrounded by more than eight electrons (e.g. ICl₄⁻ or PF₅). https://cdn.kastatic.org/ka-youtube-converted/Tkb1OemB2KI.mp4/Tkb1OemB2KI.mp4 430 Octet rule https://www.khanacademy.org/science/hs-chemistry/x2613d8165d88df5e:atomic-models-and-periodicity/x2613d8165d88df5e:lewis-diagrams/a/lewis-diagrams-and-the-octet-rule 2026-03-11T03:50:38.069700458Z Lewis diagrams and the octet rule Learn how to draw Lewis diagrams and how they help visualize patterns in electron structure and chemical reactivity. article