Year 2-acids and derivatives Flashcards
Draw 4,4-dimethylpentanoic acid.
Draw ethanamide.
Draw octane-1,8-dicarboxylic acid.
Draw propanoyl chloride.
Draw ethylbutanoate.
Draw 2,2-dimethylpentanoic acid.
Draw hexane-1,6-dicarboxylic acid
Draw methanamide.
Draw butylethanoate.
Draw butanoic anhydride.
Draw pentanoyl chloride.
Draw ethanoic anhydride.
What is the strength of HCl?
Write an equation to show aqueous HCl dissociating.
Strong acid.
How do you know that an acid is a strong acid?
Fully dissociates in water to produce H+ ions.
What strength are carboxylic acids?
Write an equation to show a carboxylic acid dissociating.
Weak acids.
How do the reactions of a strong and weak acid differ?
A strong acid’s reaction time will be faster than a weaker acid.
Write an equation of an acid reacting with a carbonate.
acid + carbonate —> salt + water + carbon dioxide
Write an equation between an acid and hydrogencarbonate.
acid + hydrogencarbonate —> salt + water +carbon dioxide
Give an example of a reaction where an acid reacts with a hydrogencarbonate.
Draw and describe (2) a carboxylate ion.
- Negative charge not fixed to one oxygen.
- Delocalised across whole COO group - so anion stable.
State the general equation of the reaction between carboxylic acid and alcohol.
Carboxylic acid + alcohol —> ester + water
State the reaction conditions and reactants (4) needed to make esters from carboxylic acid and alcohol.
- Conc. H2SO4.
- Warm in a water bath.
- Pour onto NaHCO3. (Neutralises the acid).
- Purify the ester by distilling and adding drying agent.
What are the 3 main facts and uses for esters?
- Polar, low boiling points - Used as solvents.
- Small - Used as plasticisers.
- Sweet smell - used for perfumes.
Draw and write an equation for the reaction between ethylpropanoate and a H+ ion.
Name this type of reaction.
Ester hydrolysis.
Draw and write an equation for the reaction between ethyl propanoate and a OH - ion.
Name this type of reaction.
Ester hydrolysis.
Define hydrolysis.
Split apart using water.
Draw and write an equation for the reaction between ethyl propanoate and water. H+ as catalyst.
State the 3 reaction conditions needed for acid catalysis.
- Lots of water needed. Equilibrium shifts to the right to use up water added.
- No change in equilibrium when catalyst added. Speeds up both the forward and the reverse reactions.
- Strong acid. concentrated H2SO4, can happen at room temperature.
Draw and write the 2 equations for alkaline catalysis between ethyl propanoate and water. OH- ion as catalyst.
The full reaction as shown with the equilibrium.
The other photo is the reaction that needs to be written when asked in an exam.
Describe and explain what happens in alkaline catalysis that means that we don’t need to include the equilibrium in the final equation.
The alkali catalyst reacts with the carboxylic acid being formed turning it into a carboxylate salt.
This removes the acid from the equilibrium which shifts to the right to replace it.
Therefore, the reaction goes to completion.
Define a fatty acid.
Acid with a long chain length.
State the IUPAC name for glycerol.
Propane-1,2,3-triol.
How is the structure affected if fatty acid molecules are saturated?
- Straight chain/ chain will line up.
- Strong Van der Waals forces as the fatty acids can be more compact together.
- They are usually solid as they have a high melting point
How is the structure (3) affected if the molecules in the fatty acid are unsaturated?
- There will be bends in the chain.
- There will be weaker Van der Waals forces - the fatty acids cannot pack as closely together.
- The fatty acids will be liquid (oil) because they have lower boiling points - due to Van der Waals forces.
What makes esters of glycerol with carboxylic acids fatty acids?
Long carbon chain length. >6 carbon atoms.
Label the fatty acid.
Circle is from the glycerol.
Long chains are from the fatty acid.
Draw and write the reaction between sodium hydroxide and palmitic acid triester (in the photo).
Must be boiled.
Define biodiesel. And give an example.
Mixture of methyl esters of fatty acids.
Vegetable oils with methanol.
Write and draw the general reaction between fatty acids and methanol.
State the catalyst used.
Describe what happened.
NaOH / KOH
- Vegetable oil hydrolysised (with water).
- Produces glycerol and carboxylate ion (RCOOH).
- Carboxylate ion reacts with the methanol to produce an ester.
How does soap work?
Long carbon chain is hydrophobic (doesn’t like water). This is because there are only van der Waals forces.
The long carbon chain is able to attract oils and grease.
COO-Na+ is able to attract dipoles in H2O.
The bonds are strong so when water washed away, the soap is also washed away.
Draw and write the equation associated with:
Put 5cm3 water in a small beaker and add a few drops of ethanoyl chloride.
Ethanoyl chloride + water —> ethanoic acid + hydrogen chloride
Draw and write the equation associated with:
Put 5cm3 ethanol in a small beaker and add a few drops of ethanoyl chloride.
ethanoyl chloride + ethanol —> ethyl ethanoate + hydrogen chloride
Draw and write the equation associated with:
Put 5cm3 ammonia in a small beaker and add a few drops of ethanoyl chloride.
Ethanoyl chloride + ammonia —> ethanamide + hydrogen chloride
Draw and write the equation associated with:
put 5 drops of phenylamine in a beaker and add a few drops of ethanoyl chloride.
ethanoyl chloride + phenylamine —> N-phenyl ethanamide + HCl
Draw and write the equation for the reaction between ethanoic anhydride and water.
Draw and write the equation between ethanoic anhydride and methanol.
Draw and write the equation between ethanoic acid and ammonia.
Draw and write the equation between ethanoic anhydride and phenylamine.
What type of mechanism is the reaction between acyl chlorides and acid anhydrides?
Nucleophillic substitution addition elimination mechanism
Draw the mechanism between ethanoyl chloride and methanol.
State the strength pattern for nucleophiles. Ammonia, water, alcohol and amine.
Amine > Ammonia > Alcohol > Water
Draw and write the reaction for aspirin production.
Salicyclic acid + Ethanoic anhydride —> Aspirin + Ethanoic acid
