What do all of these products have in common? ALCOHOL.

What do all of these products have in common?ALCOHOL

AlcoholObjectives

• Be able to name some of the alcohols according to the number of carbons in the hydrocarbon chain• Work out the formulae of the alcohols if the number of carbons is known• Draw the structural formula of some alcohols•Describe the properties of alcohols

Alcohols

Alcohols are a group of organic molecules which contain oxygen.

They form a HOMOLOGOUS series.

Naming the Alcohols

The names of alcohols follow the same pattern as the alkanes and alkenes.

The first part of the name relates to the number of carbons in the chain.

The second part of the name is -anol

1 carbon

2 carbons

3 carbons

4 carbons

5 carbons

Butanol.

Methanol

Pentanol

Ethanol

Propanol

Activity 1On your worksheet, complete columns 1 and 2 by writing down the number of carbons and names of the alcohols

Hint; meth, eth, prop, but, pent, hex, hept, oct, non, dec

No. of C

Atoms

Name of Alcohol

Formula

Structure

1 Methanol

2 Ethanol

3 Propanol

4 Butanol

5 Pentanol

6 Hexanol

7 Heptanol

8 Octanol

9 Nonanol

10 Decanol

Alkanes

CnH2n+2

CH4

C2H6

C3H8

C4H10

C5H12

Alkenes

CnH2n

C2H4

C3H6

C4H8

C5H10

Alcohols

CH3OH

C2H5OH

C3H7OH

C4H9OH

C5H11OH

CnH2n+1OH

Formula of Alcohols

All alcohols have the formula;

CnH2n+1OH

Methanol CH3OH

Ethanol C2H5OH

Propanol C3H7OH

Activity 2On your worksheet, complete the third column in the table by writing down the formulae of the alcohols.

Hint; Each time the carbons increase by 1, the hydrogens increase by 2

No. of C

Atoms

Name of Alcohol

Formula Structure

1 Methanol

CH3OH

2 Ethanol C2H5OH

3 Propanol

C3H7OH

4 Butanol C4H9OH

5 Pentanol

C5H11OH

6 Hexanol C6H13OH

7 Heptanol

C7H15OH

8 Octanol C8H17OH

9 Nonanol C9H19OH

10 Decanol C10H21OH

Structure of Alcohols

C – 4 bonds

H – 1 bond

O – 2 bonds (must be between a C and an H)

Methanol

C

H

O

H

H H

Ethanol

C

H

O

H

H C

H

H

H

Activity 3On your worksheet, complete the last column in the table by drawing the structure of each alcohol.

Hint; just add a carbon to the end of the chain each time…..

No. of C Atoms

Name of Alcohol

Formula Structure

1 Methanol

CH3OH HH-C-O-H H

2 Ethanol C2H5OH H HH-C-C-O-H H H

3 Propanol

C3H7OH H H HH-C-C-C-O-H H H H

4 Butanol C4H9OH H H H HH-C-C-C-C-O-H H H H H

5 Pentanol

C5H11OH H H H H HH-C-C-C-C-C-O-H H H H H H

6 Hexanol C6H13OH H H H H H H H-C-C-C-C-C-C-O-H H H H H H H

7 Heptanol

C7H15OH H H H H H H HH-C-C-C-C-C-C-C-O-H H H H H H H H

8 Octanol C8H17OH H H H H H H H HH-C-C-C-C-C-C-C-C-O-H H H H H H H H H

9 Nonanol C9H19OH H H H H H H H H HH-C-C-C-C-C-C-C-C-C-O-H H H H H H H H H H

10 Decanol C10H21OH H H H H H H H H H HH-C-C-C-C-C-C-C-C-C-C-O-H H H H H H H H H H H

Properties of Alcohols

• They are FLAMMABLE/NOT FLAMMABLE

• Their density (heaviness) INCREASES/DECREASES as the number of carbons increases

• SOME/ALL of them are poisonous

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No. of C

Atoms

Name of Alcohol

Formula

Structure

L.O.I can compare and evaluate methods for the production of ethanol.

Tuesday 18 April 2023

Chemistry drop-in clinic lunchtime Thurs 605

What might our lives be like if yeast produced methanol rather

than ethanol?

Two processes for making ethanol.

1. Fermentation with yeast.

2. Hydration of ethene.

1. Fermentation with yeast.

Sugar (glucose) Ethanol + CO2

yeast

C6H12O6 2C2H5OH + 2CO2

2. Hydration of ethene.

ethene + steam ethanolcatalyst

C2H4 + H2O C2H5OH

Told you that ethene would come in handy lad…cracking!

Hmm. I like the fermentation of

sugars to produce ethanol.

But then I like the idea of hydration of

ethene too.

But which is better?

There’s only one way to find out…

EVALUATE!

Compare and Contrast

Fermentation HydrationRenewable resource Non-renewable

Batch process ContinuousSlow Fast

Impure product Pure product

Catalyst? Catalyst

Green? Green?

Ethanol can be made by two processes, ethene reacting with ……………… under pressure in the presence of a ………………., or the fermentation

of …………… using enzymes in ………………Wordbank: catalyst, sugar, yeast, steam

How can people claim that the fermentation of plant materials does not contribute to the

increase in carbon dioxide in the air?

Why is a continuous process better than a batch process for making a product in industry?

L.O.I can compare and evaluate methods for the production of ethanol.

Tuesday 18 April 2023

Chemistry drop-in clinic lunchtime Thurs 605

What might our lives be like if yeast produced methanol rather

than ethanol?