diff --git a/docs/sch4uz.md b/docs/sch4uz.md index 24cae5f..65f87cd 100644 --- a/docs/sch4uz.md +++ b/docs/sch4uz.md @@ -515,9 +515,14 @@ Carbon is also able to bond to itself in the following ways: ### Simple hydrocarbons +!!! definition + - A **branched hydrocarbon** is one with at least one "side group" extending from the main hydrocarbon chain. + - A **functional group** is a group of atoms responsible for the characteristic properties of a molecule (e.g. C=C) + - A **homologous series** is a family of organic compounds with the same functional group but the hydrocarbon chain length changes by 1 $\ce{CH2}$ group. + These only contain carbon and hydrogen. -**Alkanes** only contain single bonds between carbons, and are named with the number of carbons with the suffix "-ane". +**Alkanes** are a homologous series that only contain single bonds between carbons, and are named with the number of carbons with the suffix "-ane". (Source: Kognity) @@ -566,6 +571,63 @@ A **line diagram** or **skeletal structural formula** removes carbons and hydrog These are the ways to represent pentane, $\ce{C5H12}$. The structural formula is mislabeled as a condensed structural diagram. (Source: Kognity) +### General nomenclature + +To name an organic compound: + +1. Find the **longest acyclic chain** of carbon atoms as the parent chain. +2. Assign numbers from 1 to $n$ for each carbon atom in the parent chain. + - The numbers should be arranged in a way that the highest priority functional group in the chain is assigned the lowest number possible. + - Apply the **first branch rule** only if there is a tie: If there are side chains, the parent chain should be numbered such that the location of any side chains have the lowest number possible. + - If there is a tie, the location with the most branches wins. + - If there is a tie, the rest of the chain is compared in sequence applying the first branch rule. + - If there is a tie, the first location with the side chain group name that is alphabetically greater wins. + - If there is a tie, it doesn't matter which side is picked as the whole thing is symmetrical. +3. Name the main chain based on the name of the functional group and location number for the functional group in the format "number-name". +4. Name the side groups. + - If the group is not carbon, name it by its identity. + - Otherwise, name the hydrocarbon based on the number of carbons in the side group with the ending "yl". + - If there is more than one identical side group in the **whole chain**, combine their numbers and names with a Greek prefix. + - Assign a number representing the carbon atom of the parent chain that the side group is attached to in the form "numbers-name". +5. Arrange the name with each side group with their numbers in alphabetical order, discounting any prefixes due to duplicates, followed by the parent chain. +6. Join everything together: + - Drop the ending vowel from the prefix if there is a double vowel unless it is "i". + - Separate numbers from words with dashes. + - Separate numbers from numbers with commas. + - Do not separate words from words. + +!!! tip + In hydrocarbons: + + - Atoms with double or triple bonds share equal priority as the highest functional group. + - The main chain will be named as an alkane if there are only single bonds. + - If there is exactly one double or triple bond, it will be named as an alkene or alkyne with its position inserted between the prefix and ending. + - e.g., "pentane", "pent-2-ene" + - If there are multiple double or triple bonds, their numbers are also included, but an "a" is appended to the prefix and a Greek prefix added to the suffix. + - e.g., "penta-1,3-diene", "hexa-1,3,5-triyne" + - If there are both double and triple bonds, the "-ene" becomes "-en" and is always before "-yne". + - e.g., "pent-4-en-2-yne" + +!!! example + tf + +Other **side chains** with equal priority as double or triple bonds *in side chains* include: + + - halogens, which have their "-ine" suffix replaced with "o" (e.g., "chloro") + - $\ce{NO2}$: "nitro-" + - benzene (as a side chain): "phenyl" + +If there is no other option and there is a **branched side chain**, name it based on the total number of carbon atoms in the side chain. + +!!! example + tf + +### Cyclic hydrocarbons + + + +### Isomers and functional groups + ## Resources - [IB Chemistry Data Booklet](/resources/g11/ib-chemistry-data-booklet.pdf)