Organics – Non-Hydrocarbons

1. Organics – Non-Hydrocarbons Haloalkanes – uses and sources Alcohols – uses, sources and reactions Carboxylic acids – uses, sources and reactions Esters – uses, sources and reactions Types of reactions - A summary

2. Haloalkanes – Uses, sources and reactions • Haloalkanes are saturated organic molecules with halogen atoms attached. Sources • They can be made by adding halogens or hydrogen halides to unsaturated organic molecules Uses • Haloalkanes can be used as solvents and they were once used as refrigerant gases (CFCs) Reactions • We don’t have to worry about reactions of haloalkanes in this section of work

3. Alcohols – Uses and sources • Alcohols (also known as alkanols) are similar to alkanes except they have an –OH group attached somewhere in their structure. They are miscible (when two liquids ‘dissolve’) in both water and non-polar substances Sources • Ethanol can be made by fermentation or the hydration of ethene • Methanol can be made from natural gas (methane) Uses • Alcohols can be used as fuels, solvents and in beverages (ethanol only)

4. Alcohols – Structure • The structure of alcohols is very important to recognise because only certain types of alcohols react in a certain way. • Alcohols react differently based on the sort of carbon that the –OH group is bonded to. See the three chemicals below? What makes these three molecules different? • Primary alcohols – the carbon is bonded to one other carbon • Secondary alcohols – the carbon is bonded to two other carbons • Tertiary alcohols – the carbon is bonded to three other carbons Primary Secondary Tertiary

5. Alcohols - Reactions • Combustion – Alcohols burn without producing soot or smoke (carbon) • Oxidation – Primary alcohols can be oxidised to create carboxylic acids. We can use acidified dichromate or acidified permanganate as oxidising agents • Elimination – As you might have guessed elimination reactions remove parts of the alcohol. In this case we remove the –OH group and one other hydrogen using concentrated sulfuric acid. An alkene is the product of an elimination reaction

6. Carboxylic Acids – Uses and sources • Carboxylic acids are weak acids. The short chained ones are miscible in water, but longer chained ones do not dissolve. Sources • They can be made by oxidising primary alcohols • Carboxylic acids are also produced by natural processes such as the oxidation of wine. Some ants, wasps and nettles also produce methanoic acid as a way of making people miserable Uses • These acids can be used in food stuffs (e.g. Acidity regulator 260) • They are also used in the production of fruit flavours (see the Ester section)

7. Carboxylic Acids – Reactions • Neutralisation – Because they are acids they will neutralise with bases to produce a salt and water. The salts names always end in –oate e.g. sodium ethanoate • Esterification – When we mix an alcohol with a carboxylic acid (and some concentrated sulfuric acid) we get an ester formed:

8. Esters – Uses and sources • Esters are non-soluble in water. As seen earlier they are a product of reacting an alcohol with a carboxylic acid Uses • Esters have a number of uses. The main one is in the production of fruit flavours – some smell nice and fruity • Esters can also make good solvents (i.e. nail polish remover) • Esterification is also used to produce fats and oils Sources • Esters are made by fruits (for flavour) and by all living things (fats and oils) • Also as discussed earlier we can make them in the lab

9. Esters - Reactions • Hydrolysis – This type of reaction involves water (hydro) breaking (lysis). In other words we get water, break it up and shove it inside the ester somehow. The result is that the water is absorbed and the ester breaks into the acid and the alcohol again: • Saponifaction – This is the production of soap from a fat (a molecule containing three esters) reacting with NaOH.

10. Types of Reactions – a summary • Match the terms with the summaries below: * What reaction(s) could be describes as dehydration reactions?

11. Reaction Summary Ex.