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What is the name of this carboxylic acid? CH3CH(CH3)CH2COOH

3-methylbutanoic acid

1

Name this: (COOH)2

Ethanedioic acid

2

What do carboxylic acids form when they dissociate in aqueous solution?

oxonium ions, carboxylate ions

3

What do carboxylic acids form when they react with bases?

Salts

4

How do you form an ester?
What is the reaction called?

Reflux a carboxylic acid with an alcohol, using a strong acid catalyst
It is esterification reaction and is reversible

5

What derivatives are formed from carboxylic acids?

ester, acyl chloride, amide, acid anhydride

6

What is the test for phenols?

Neutral iron(iii) chloride solution forms a purple complex

7

What is the order of acidic strength fir alchols, phenols, carboxylic acids and water?

ethanol, water, phenol, ethanoic acid

8

Why are phenols and carboxylic acids more acidic?

More stable anion as the negative charge is delocalised across several atoms

9

What is the reaction of phenol and NaOH?

Forms salt C6H5O- Na+ and water

10

Reaction of ethanoic acid and Na2CO3?

Forms salt CH3COO-Na+, CO2 and water

11

Equation for limewater test?

CO2+Ca(OH)2 ----> CaCO3 (cloudy precipitate + water

12

How is ester hydrolysis carries out?

Acid hydrolysis- sulfuric acid catalyst
Alkaline hydrolysis- NaOH (forms carboxylate salt instead of acid)

13

Why is alkaline hydrolysis of esters preferred?

The reaction goes to completion

14

How do phenols form esters?

By reacting with acyl chlorides and rtp or acid anhydrides under reflux in anhydrous conditions for both.

15

How do you name an ester?

The first part is from the alcohol and the second is from the acid. The carbonyl group C=O is always from the acid.

16

Name this ester: HCOOCH2CH2CH3

Propyl methanoate

17

What is the order of atom economy of reactions? (descending)

Rearrangement and addition, substitution and condensation, elimination.

18

Equation for % atom economy?

Mr of useful product/ Mr of reactants x 100

19

what functional group do both aldehydes and ketones contain?

carbonyl group C=O

20

What reactants are needed to make an aldehyde?

Primary alcohol and acidified potassium dichromate
Distill off aldehyde immediately to prevent further oxidation

21

What product do you get when a primary alcohol is heated under reflux with acidified potassium dichromate?

Carboxylic acid

22

How do you make a ketone?

Reflux secondary alcohol with acidified potassium dichromate

23

what colour change happens in this reaction and does it happen with aldehydes or ketones?
Cr2O7 (2-) + 14H+ + 6e- ---> 2Cr3+ + 7H20

Dichromate ion is reduced, solution changes from orange to green in the presence of aldehydes (or primary and secondary alcohols)

24

What is Fehling's solution and what is it used for?

It is a solution of blue Cu2+ ions and alkali. It is used to distinguish between aldehydes and ketones, in aldehydes the Cu2+ is reduced to Cu+ turning from blue to an orange brown precipiatate. In ketones there is no colour change.

25

What is used to reduce aldehydes and ketones back to their alcohols?

NaBH4 sodium tetrahydridoborate

26

What reaction do aldehydes and ketones undergo in the presence of HCN and an alkali? What is the nucleophile?

Nucleophilic addition, CN-

27

what is the product of the reaction of an aldehyde or ketone with HCN ?

2-hudroxynitrile or cyanohydrin

28

What is the definition of an acid?

a proton donor

29

what is a base?

a proton acceptor

30

what is an alkali?

a base that dissolves in water to produce OH- ions

31

which is the acid and which is the base in this reaction?
HNO3 + H2O ---> NO3-+ H3O+

HNO3 is acid
H2O is base

32

what ions do acids become in aqueous solution?

oxonium ions H3O+

33

What is a conjugate acid?

A species which in the reverse reaction accepts protons

34

What does it mean if a species is amphoteric?

they can act as both an acid and a base

35

What are strong acids and how strong is their conjugate base?

Powerful proton donators and a weak conjugate base

36

what is the molecular ion?

Ion produced when the parent molecule has lost just one electron.
It is the peak with the greatest m/z on the spectrum.

37

What labels are on the axis of a mass spectrum?

x-axis is mass to charge ratio m/z
y-axis is intensity

38

what is the process by which the molecular ion breaks up?

fragmentation

39

what does the molecular ion tell you?

the molecular mass of the compound

40

How accurate is high resolution mass spectrometry and what is it used for?

4.d.p, distinguishes between compounds that appear to have the same Mr by low resolution mass spectroscopy.