Unit 2 - Everyday Consumer Products Flashcards
Describe how to identify an alcohol:
From the name
From a structure
Name ends in “-ol”
Structure contains the hydroxyl group -O-H
What is the general formula of alcohols?(also known as alkanols)
CnH2n+1OH
OR
CnH2n+2O
What are the steps need to name alcohols?
Identify longest chain of carbons (meth- ,eth- etc)
The hydroxyl functional group is the most important part of the molecule and the carbon chain is numbered to give it the lowest branch number
Add -ol to the end
Examples Propan-2-ol and Pentan-1-ol
Describe the chemical properties and uses of alcohols.
Chemical properties of alcohols include that they are flammable and they react with carboxylic acids to form esters.
Alcohols are used as fuels as they are highly flammable and burn with very clean flames.
Used as solvents.
Describe how to identify a carboxylic acid:
From the name
From a structure
The name ends in -oic acid
The structure contains the carboxyl functional group
–COOH
What is the general formula of carboxylic acids?(also known as alkanoic acids)
CnH2nO2
What are the steps need to name carboxylic acids?
Identify longest chain of carbons (meth- ,eth- etc)
The position of the carboxyl group does not need to be identified with a number, as it is always found at the end of the carbon chain, and so is on the first carbon.
Add oic acid to the end
Examples Methanoic acid and Butanoic acid
Describe the chemical properties and uses of carboxylic acids.
Chemical properties of carboxylic acids to include
1. pH
Reactions with metals, oxides, hydroxides and carbonates
reaction with alcohols to form esters
Vinegar is a solution of ethanoic acid. Vinegar is used in household cleaning products and as a preservative in the food industry.
Identify the: Alcohol and Carboxylic Acid
from the names below
(i) Heptan-2-ol
(ii) Octanoic acid
(i) Heptan-2-ol = Alcohol
(ii) Octanoic acid = Carboxylic Acid
dentify the: Alcohols and Carboxylic Acids
from the formulae below
(i) H3C-CH2-CH(OH)-CH3
(ii) H3C-CH2-COOCH3
(iii) H3C-CH2-COOH
(i) H3C-CH2-CH(OH)-CH3 = Alcohol
(ii) H3C-CH2-COOCH3 = Carboxylic Acid
(iii) H3C-CH2-COOH = Carboxylic Acid
Comparing ethane, ethene, ethanol and ethanoic acid shows that ethanoic acid has the highest MP and BP.
Why?
This is because the ethanoic acid molecules are held more tightly together (by intermolecular forces) and require more energy to separate.
Links to bonding topic from unit 1
Methane is a covalent molecular substance.
It has a low boiling point and is a gas at room temperature.
Explain why methane is a gas at room temperature.
Weak intermolecular attractions or weak bond attraction between molecules
Links to bonding topic from unit 1
