17.8 The Carboxylic Acids Flashcards
What is the functional group of carboxylic acids and what are they also called?
COOH
It is called carboxyl group
What is the homologous series formula for carboxylic acids?
CnH2nO2
How can you make ethanoic acid?
By oxidizing Ethanol
The oxidation Of ethanol to make ethanoic acid can be carried out in 2 ways. What are thy?
Fermentation Oxidizing agent (chemical)
How can you ferment ethanol to ethanoic acid?
The ethanol is left in air, bacteria do the oxidization to ethanoic acid.
What is acid fermentation?
When an alcohol is oxidized by bacteria to make a carboxylic acid.
Acid fermentation is used to make ginger ( a dilute sol. Of ethanoic acid) ginger is first foods life apples , rice, honey which are fermented to give ethanol.
Who is ethanoic acid formed by oxidizing agent, chemical way?
Ethanol can be oxidized by warming it with a powerful oxidizing agent potassium manganate (VII) in the presence of acid.
The manganate (VII) ions are themselves reduced to Mn2+ ions= COULD LOUR CHANGE COLOURLESS. The acid added provides the H+ ions for the reaction.
MnO4- + 8H+ +5e- -> Mn2+ + 4H2O
What colour does litmus paper turn in ethanoic acid?
Red
What will form when a carboxylic acid reacts with metals, bases, and carbonates?
Salts
CH3COOH + NaOH -> CH3COONa + H2O
Name the salt
Sodium ethanoate
How can an acid be a weak or strong acid?
By the amount of molecules that dissociate when in water.
More dissociation = more acidic
Less dissociation = less acidic
What is an ester?
The product of the reactants
Alcohol and a carboxylic acid
What are the main points about the reaction that produces ESTER?
2 molecules have joined together with the losses of a small molecules water= CONDENSATION REACTION (since water is lost)
The reaction is reversible, so concentrated sulphuric acid (H2SO4) acts as a catalyst
The alcohol part comes FIRST in the name and SECOND in the formula
Propyl ethanoate smells like pears, most eaters smell/ taste good, so they are added to shampoos, ice cream etc
What is the equation for the reaction of ETHANOIC ACID + PROPANOL?
CH3COOH + C3H7OH CH3COOC3H7 + H2O
