Exam (elaborations)
module 6 organic chemistry Exam 2024/2025 Questions With Completed & Verified Solutions.
- Course
- Institution
module 6 organic chemistry Exam 2024/2025 Questions With Completed & Verified Solutions.
[Show more]
Content preview
module 6 organic chemistrykekulē model - ANS suggested that atoms joined by alternate single and double bonds
evidence against kekule - ANS 1. lack of reactivity of benzene
2. length of bonds
3. hydrogenation enthalpies
lack of reactivity - ANS does not undergo electrophilic addition reactions
does not decolourise bromine
delocalised model of benzene - ANS 1. planar, cyclic, hexagonal hydrocarbon
2. overlapping of p-orbitals creates a system of pi-bonds
3. electrons are delocalised
phenol acts as... - ANS a weak acid
phenol vs benzene - ANS phenol is more reactive due to the lone pair of electrons from the
oxygen p-orbital being donated into the pi-system
the electron density of the ring is increased
oxidation of aldehydes - ANS to carboxylic acid
ketones and aldehydes undergo - ANS nucleophilic addition
reducing agent - ANS NaBH4 sodium tetrahydridoborate(iii)
ketone reduced to - ANS secondary alcohol
aldehyde reduced to - ANS primary alcohol
reactions of carbonyls with HCN - ANS forms hydroxynitriles
testing for carbonyl group - ANS use 2,4-DNP
1. ad 5cm depth of 2,4-DNP into a test tube
2. add three drops of unknown compound
3. no crystals formed, add a few drops of sulfuric acid
4. yellow/orange ppt indicated presence of a carbonyl
reaction with 2.4-DNP - ANS condensation reaction
, tollen's reagent - ANS silver nitrate in aqueous ammonia, in presence of aldehyde a silver mirror
is produced
testing for aldehyde group with Tollen's - ANS 1. add 3cm of aq silver nitrate
2. add aq sodium hydroxide until a brown ppt is formed
3. add dilute ammonia until brown ppt dissolves
4. add unknown solution to clean tube
5. add equal vol of tollens
silver ions - ANS act as an oxidising agent in presence of ammonia, reduced to silver
carboxylic acids are classified as... - ANS weak acids
redox of carboxylic acid and metals - ANS form hydrogen gas and carboxylate salt, metal
dissolves and effervescence
neutralisation of COOH and metal oxides - ANS salt and water
tests for carboxyl group - ANS neutralisation with carbonates
naming esters - ANS alcohol then carboxylic acid
acid anhydride - ANS formed from removal of water from two carboxyls
esterification - ANS alcohol and carboxylic acid to form an ester
acid hydrolysis of esters - ANS heated under reflux with dilute aq acid
produce carboxylic acid and alcohol
alkaline hydrolysis of esters - ANS reflux with aq hydroxide ions
form carboxyl ion and alcohol
acyl chloride prep - ANS thionyl chloride
acyl chloride and water - ANS makes carboxylic acid
ammonia and amines act as - ANS nucleophiles by donating the lone pair of electrons on the
nitrogen to an electron-deficient species
ammonia and acyl chloride - ANS primary amide
primary amine and acyl chloride - ANS form secondary amide
amines behave as - ANS bases as the lone pair of electrons can accept a proton
The benefits of buying summaries with Stuvia:
Guaranteed quality through customer reviews
Stuvia customers have reviewed more than 700,000 summaries. This how you know that you are buying the best documents.
Quick and easy check-out
You can quickly pay through credit card or Stuvia-credit for the summaries. There is no membership needed.
Focus on what matters
Your fellow students write the study notes themselves, which is why the documents are always reliable and up-to-date. This ensures you quickly get to the core!
Frequently asked questions
What do I get when I buy this document?
You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.
Satisfaction guarantee: how does it work?
Our satisfaction guarantee ensures that you always find a study document that suits you well. You fill out a form, and our customer service team takes care of the rest.
Who am I buying these notes from?
Stuvia is a marketplace, so you are not buying this document from us, but from seller LEWIS12. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy these notes for $9.99. You're not tied to anything after your purchase.
Can Stuvia be trusted?
4.6 stars on Google & Trustpilot (+1000 reviews)
77857 documents were sold in the last 30 days
Founded in 2010, the go-to place to buy study notes for 14 years now
