From e4782e12efa68ef1d99f54aa4649fc012829519c Mon Sep 17 00:00:00 2001 From: eggy Date: Mon, 5 Oct 2020 21:25:02 -0400 Subject: [PATCH] chem: add bonding intro --- docs/sch3uz.md | 20 ++++++++++++++++++++ 1 file changed, 20 insertions(+) diff --git a/docs/sch3uz.md b/docs/sch3uz.md index 68ef3df..7f86908 100644 --- a/docs/sch3uz.md +++ b/docs/sch3uz.md @@ -226,9 +226,29 @@ Down a period, the number of shells occupied by the electrons increases, so vale ## 4.0 - Chemical bonding and structure +A chemical bond consists of the strong electronic interactions of the **valence** electrons between atoms that hold the atoms closer together. This only occurs if the atoms would reduce their potential energy by bonding. + +!!! reminder + - Metal + metal = metallic bond + - Metal + non-metal = ionic bond + - Non-metal + non-metal = covalent bond + +### 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**. + +If ΔEN is: + + - less than 0.5, it behaves like a **pure covalent** bond + - between 0.5 and 1.7, it behaves like a **polar covalent** bond + - greater than 1.7, it behaves like an **ionic** bond + ## 4.1 - Ionic bonding and structure +Ionic bonds are the interaction of **oppositely charged ions**. Electrons are transferred first, and then the bond forms via the attraction of the now-positive and negative ions. This reduces the potential energy of the ions and therefore increases their stability. +!!! warning + When expressing ionic bonds in a Lewis dot diagram, the oppositely-charged ions must *never* be placed next to one another. ## 4.2 - Covalent bonding