Esterification, Gibbs Energy Flashcards

1
Q

What is the name of the ester made up of?

A

The first part from the alcohol, the second part from the carboxylic acid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is the functional group of an ester?

A

-COO-

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

How do you make an ester from an alcohol and carboxylic acid?

A

Heat a carboxylic acid with an alcohol in the presence of an acid catalyst, such as conc HCl

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is esterification?

A

A reaction in which you get an ester

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

How do you make ethyl ethanoate?

A

Reflux ethanoic acid with ethanol and conc sulfuric acid as a catalyst

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

As the reaction to produce an ester is reversible, what do you have to use to separate the product when its formed?

A

You have to use distillation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Why do you mix the ester product formed with sodium carbonate?

A

To react with any carboxylic acid that might of snuck in

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What happens when the ester product is reacted with sodium carbonate?

A

The ethyl ethanoate forms a layer on top of the aqueous layer which can be easily separated using a separating funnel

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is ethyl ethanoate often used as?

A

A solvent in chromatography, and often has a pineapple flavouring

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What is acid hydrolysis?

A

Where the ester is split into an acid and an alcohol

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Why is the reaction between ethanoic acid and ethanol a condensation reaction?

A

A small molecule (water) is released

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

How do you perform acid hydrolysis?

A

Reflux ester with dilute HCl, which forms an alcohol and a carboxylic acid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What is base hydrolysis?

A

When you reflux the ester with a dilute alkali, such as dilute NaOH

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What does base hydrolysis form?

A

A carboxylate ion and an alcohol

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What do diols contain?

A

2 OH groups

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What do dicarboxylic acids contain?

A

2 COOH groups

17
Q

What do diols and dicarboxylic acids react to form?

A

Long esters chains, called polyesters

18
Q

What is condensation polymersiation?

A

When dicarboxylic acids and diols react to form long ester chains (polyesters)

19
Q

What is eliminated when dicarboxylic acids react with diols?

A

A water molecule

20
Q

What are some properties of polyester fibres?

A

They are strong and flexible

21
Q

What does delta G mean?

A

The free energy change

22
Q

What does delta G equal?

A

Change in enthalpy - Temp X system entropy change

23
Q

For a reaction to be feasible, what does delat G have to be?

A

Negative

24
Q

In terms of equilibrium constants, what does delta G equal?

A

Delta G = -RT lnk

25
Q

Why doesn’t a negative Gibbes energy change guarentee a reaction?

A

The reaction may have a very high activation energy2