Organic ChemistryC3.5

Love, Heba

Homologous Series

Basic Facts…A homologous series is a group of compounds with the

same general formula - The compounds in a series contain the same elements and have similar molecular structures

Their physical properties change gradually as the compounds increase in size.

Example: The boiling points of compounds in a homologues series increases as the size of the molecules increase.

You probably already know this…

Name No. of Carbons

Meth- 1 Eth- 2

Prop- 3

Alkanes & AlkenesAlkanes ( up to 4 carbon atoms per molecule)

Alkenes ( up to 3 carbon atoms per molecule)

Single bonds Double Bonds ( up to 3 carbon molecules per

Saturated Unsaturated

General formula: General formula:

Doesn’t de-colourise bromine Water

Causes bromine water to turn Colourless

Example: Butane has 4 carbon atoms.

4x2+2 = 10 Hydrogen

Example: Propene 6 hydrogen , 3 carbon

Butane: Propene:

Alcohols ( -OH) General Formula :

up to 3 carbons atoms per molecule

Methanol Ethanol Propanol

Carboxylic Acid - COOH

General Formula :

up to 3 carbons atoms per molecule

Methanoic acid ( NOTE FOR THIS N=0 )

Ethonoic acid N=1 Propanoic acid N=2

Production of Ethanol

Ethanol can be made byFermentation

This includes using YEAST to convert CARBOHYDRATES ( SUGARS) into ALCOHOL

𝐶6 𝐻12𝑂6→2𝐶2𝐻5𝑂𝐻+2𝐶𝑂2

GLUCOSE ETHANOL CARBONDIOXIDE

Note:

- The Carbohydrate can come from any source Often Sugar cane and sugar beet

- The yeast cells contain an enzyme ( a catalyst speeding up the reaction… obv! )

The process… Mix Yeast and solution of Carbohydrate ( e.g. glucose ) in a

clean container.

Seal the container and leave in a warm place

Reason of sealing – To keep mixture in anaerobic conditions ( no oxygen ). If there's oxygen it will convert the ethanol into

ethanoic acid ( vinegar) Ya don’t want that!

Keep at warm place ( e.g. between 30 and 40 degrees ) this ensures fermentation happens at a fast rate b/c its optimum

temperature for enzymes… TOO HOT = ENZYMES DENATURES.

When the concentration of ethanol is around 10/20% the reaction stops because the Yeast is killed off by the alcohol.

Yeast will fall to the bottom of the container, collect alcohol from the top.

To increase percentage created…

Distill fermented mixture. Brandy is distilled from wine, whisky is distilled from fermented Grain and Vodka’s distilled from fermented grain or potatoes!

Different types of HARAM alcoholic drink contain different percentages of ethanol

E.G beer is about 4% while some spirits are around 40%

Fractional Distillation ( making ethanol more concentrated)

Remember: Fermentation produces dilute ethanol below 20% concentration ,

Fractional distillation makes dilute ethanol more concentrated… :

Fractional distillation

1)Fractional distillation separates mixtures using heat2) We want to separate water from ethanol 3) Ethanol has lower boiling point than water 4) When mixture is heated, ethanol evaporates and the vapour rises up the fractionating column, while the water stays there- as liquid 5) A Liebig condenser is used to condense the ethanol vapour by cooling it. 6) The concentrated ethanol can then be collected in a separate flask…

Pro’s & Con’s - Fermentation

Renewable source ( sugar cane and sugar beet) wont run out

Quality of ethanol solution isn't too greatits expensive to concentrate and purify the Ethanol

Production and Issues of Ethanol

Ethene is used to make Ethanol…

Ethene can be reacted with steam to produce Ethanol.

Ethene + Water ( steam) 𝐶2 𝐻4+𝐻2𝑂→𝐶2𝐻5𝑂𝐻

𝐻2𝑂

Ethene is produced from cracking crude oil

Pros & Cons of using Ethene…

At the time, relatively cheap process because Ethene is quite cheap and not much of it is wasted

Its made in a large chemical plant , it can be made continuously and quickly. The quality is very good and doesn’t need further processing unlike fermentation

Ethene is produced from crude oil , it’s from a non-renewable source. Will run out! This means that making ethanol using Ethene will become more expensive!

Effects of Alcohol ON THE BODY

Reduces activity of nervous system. Increases reaction times, impaired judgement , poor

balance, coordination, unconsciousness Excess Alcohol causes dehydration can damage brain

cellsDamaged brain cells = drop brain function, long-term

memory lossSevere damage to liver, leading to liver disease

This is why my lovelies its HARAM

Effects of Alcohol ON SOCIETY

Aggressive behaviourFamily breakdown , loss of job and may become homelessAddiction – AlcoholismHaving sex with random people – increasing chance of

STI’s Drunk drivers can cause accidents leading to death and

serious injuryEconomic costs – A&E, more Police etc.…

Ethene and Ethanoic Acid

WILL UPLOAD LAST TWO SECTIONS BY 2 PM TMO