100% satisfaction guarantee Immediately available after payment Both online and in PDF No strings attached
logo-home
Unit 14 Aim A: Reactions and Properties of Functional Group Compounds Assignment (DISTINCTION) $7.20   Add to cart

Essay

Unit 14 Aim A: Reactions and Properties of Functional Group Compounds Assignment (DISTINCTION)

1 review
 55 views  1 purchase
  • Course
  • Institution

This is my distinction grade assignment for unit 14 aim A on the reactions and properties of functional group compounds, including alcohols, aldehydes, ketones and more. All criteria were met and I was awarded distinction. If you have any questions or concerns, please do not hesitate to get in ...

[Show more]

Preview 2 out of 7  pages

  • June 21, 2023
  • 7
  • 2022/2023
  • Essay
  • Unknown
  • A+

1  review

review-writer-avatar

By: ivandrago • 7 months ago

avatar-seller
Functional Group Compounds
Part 1: Reactions of Organic Compounds

Question 1: Halogenoalkanes and their reactions

Halogenoalkanes are a homologous series of molecules which consist of carbon, hydrogen and
halogen atoms. Carbon atoms have a higher electronegativity than halogen atoms, which results in a
polar molecule where there is a slightly positive charge on the carbon atom and a slightly negative
charge on the attached halogen atom. This slight positive charge on the carbon attracts negatively
charged nucleophiles – electron rich molecules which donate a pair of electrons. When the carbon is
fully saturated, meaning it has made all four of its possible bonds, one group will be removed,
known as the leaving group, which results in the nucleophilic substitution reaction.

Halogenoalkanes increase in reactivity down the group, due to the increasing bond length which
allows bonds to be broken more easily; in this case, that would mean that the nucleophile can
substitute the halogen group more easily. Since iodine is lower in the group than chlorine, it forms
longer bonds which are broken more easily, making iodoalkanes more reactive than chloroalkanes
(1).




Figure 1: Nucleophilic Substitution Reaction of 1-Chloropropane and NaOH

Figure 1 above shows the nucleophilic substitution reaction between 1-chloropropane and aqueous
sodium hydroxide. This reaction requires sodium hydroxide to be dissolved in a solvent so that the
hydroxide ion is free to move. It also requires heat to be added, so it is usually done using a reflux
system, to prevent the loss of reagents whilst heating.




Figure 2: Mechanism of Nucleophilic Substitution Reaction of 1-Chloropropane and NaOH

Figure 2 shows the mechanism of the nucleophilic substitution reaction which is shown in figure 1.
This reaction is in two steps; step one involves the polar bond between carbon and the chloride
group breaking, forming a carbocation and negative chloride ion. In step two, the OH nucleophile
from aqueous sodium hydroxide attacks the carbocation, forming propan-1-ol.

, Figure 3: Nucleophilic Substitution Reaction of 2-bromobutane and Ammonia

Figure 3 above shows the nucleophilic substitution reaction between 2-bromobutane and ammonia.
The 2-bromobutane must be heated with a concentrated solution of ammonia in ethanol. This
reaction must take place in a sealed tube to prevent ammonia gas from escaping as it has a boiling
point of -33°C so would remain a gas even in the Leibig condenser (2).

The nucleophilic substitution reaction occurs when the halogen is in the primary or secondary
position. When the halogen is in the secondary or tertiary position, the halogen atom may be expelled
from the molecule, in a reaction known as the nucleophilic elimination reaction (3). When it is in the
secondary position, a higher concentration of ethanol in the solvent, higher temperatures and higher
concentrations of sodium/potassium hydroxide solutions all mean that the reaction is more likely to
be an elimination reaction rather than substitution. These conditions encourage the elimination of the
halogen over the substitution because there is more energy and more concentrated solvent in the
reaction, allowing it to expel the halogen atom without the need to replace it.




Figure 4: Nucleophilic Elimination Reaction of 2-bromopropane and NaOH

Figure 4 shows the nucleophilic elimination reaction between 2-bromopropane and sodium
hydroxide. In the nucleophilic elimination reaction, the halogen atom is expelled and forms an anion
with a lone pair of electrons, leaving the carbon free, unlike the substitution reaction, in which the
nucleophile bonds with the carbon atom in place of the halogen atom. This occurs when the hydroxide
ion attacks a hydrogen ion, which it has a tendency to react with to form water. Because of this, the
electrons must rearrange, expelling the halogen atom and forming a double bond between the carbon
which it was bonded to and the adjacent carbon. The products of this reaction are an alkene, a halogen
anion with a lone pair of electrons, and a water molecule. This mechanism can be seen in figure 5
below.




Figure 5: Mechanism of Nucleophilic Elimination Reaction

The benefits of buying summaries with Stuvia:

Guaranteed quality through customer reviews

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

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

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 emilybullas. Stuvia facilitates payment to the seller.

Will I be stuck with a subscription?

No, you only buy these notes for $7.20. You're not tied to anything after your purchase.

Can Stuvia be trusted?

4.6 stars on Google & Trustpilot (+1000 reviews)

62890 documents were sold in the last 30 days

Founded in 2010, the go-to place to buy study notes for 14 years now

Start selling
$7.20  1x  sold
  • (1)
  Add to cart