Carboxylic Acids and Esters Flashcards Preview

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Flashcards in Carboxylic Acids and Esters Deck (18):

What functional group do carboxylic acids contain?

The carboxyl functional group -COOH


How do you name carboxylic acids?

Find and name the longer alkane chain, take off the 'e' and add '-oic acid'.


Why are carboxylic acids weak acids?

In water they partially dissociate into carboxylate ions and H+ ions.


Why are carboxylic acids polar molecules?

Since electrons are drawn towards the O atoms- this makes small carboxylic acids very soluble in water, as they form hydrogen bonds with the water molecules.


Carboxylic acids react with more reactive metals to form...

A salt and hydrogen gas


Carboxylic acids react with carbonates to form...

A salt, carbon dioxide and water


Carboxylic acids are neutralised by bases to form...

Salts and water


What functional group do esters have?



How is an ester made?

By reacting an alcohol with a carboxylic acid.


How is an ester named?

It's made up of two parts- the first bit comes from the alcohol and the second bit from the carboxylic acid.


In what two ways can you make esters?

From alcohols and carboxylic acidsFrom alcohols and acid anhydrides


How can you make esters from alcohols and carboxylic acids?

If you heat a carboxylic acid with an alcohol in the presence of an acid catalyst, you get an ester.Conc sulfuric acid is used as a catalyst- esterification reaction.Reaction is reversible so you need to separate out the product as it's formed.


How can you make esters from alcohols and acid anhydrides?

1) The acid anhydride is warmed with the alcohol.2) The products are an ester and a carboxylic acid which can be separated by fractional distillation.


Where are esters used?

As food flavourings and perfumes.


Esters are hydrolysed to form what?



What are the two ways to hydrolyse esters?

Acid hydrolysis and base hydrolysis.


What is acid hydrolysis?

Acid hydrolysis splits the ester into a carboxylic acid and an alcohol. You have to reflux the ester with a dilute acid, such as hydrochloric or sulfuric.


What is base hydrolysis?

You have to reflux the ester with a dilute alkali, such as sodium hydroxide. You get a carboxylate salt and an alcohol.