From 985fbff677ca81cf710de9b130f63e2d32457d95 Mon Sep 17 00:00:00 2001 From: eggy Date: Thu, 8 Oct 2020 11:12:06 -0400 Subject: [PATCH] chem: add lewis tips and tentative dative bonds --- docs/sch3uz.md | 15 ++++++++++++++- 1 file changed, 14 insertions(+), 1 deletion(-) diff --git a/docs/sch3uz.md b/docs/sch3uz.md index 12b0943..559948c 100644 --- a/docs/sch3uz.md +++ b/docs/sch3uz.md @@ -238,6 +238,15 @@ A chemical bond consists of the strong electronic interactions of the **valence* - Metal + non-metal = ionic bond - Non-metal + non-metal = covalent bond +!!! reminder + When drawing a Lewis **dot diagram**, covalent bonds must be represented as two adjacent dots. When drawing a Lewis **structure**, covalent bonds must be represented as lines connecting the atoms. + + If the process stage is required: + + - Electrons destined to be shared must be encircled. + - Electrons to be transferred must have arrows pointing to their destination. + - x'es are used to represent additional electrons that have an unknown source. + ### Percentage ionic character Bonding is a spectrum. The percentage ionic character of a chemical bond shows roughly the amount of time valence electrons spend near an atom or ion in a bond. The difference between two elements' electronegativity (ΔEN) indicates how covalent and how ionic the bond **behaves**. @@ -293,9 +302,13 @@ The **bonding capacity** of a non-metal describes the number of covalent bonds i The number of covalent bonds required is then: $$\frac{\text{needed} - \text{have}}{2}$$ -The number of lone pairs left over is: +The number of lone pairs (pairs of un-bonded electrons) left over is: $$\frac{\text{have} - 2 × \text{bonds required}}{2}$$ +### Dative covalent bonds + +Sometimes, one atom in a covalent bond may contribute both electrons in a shared pair. + ## 4.3 - Covalent structures ## 4.4 - Intermolecular forces