ALKANAL (ALDEHID) : TATA NAMA, ISOMER, REAKSI KIMIA, REAKSI SINTESIS (PEMBUATAN), APLIKASI

Summary

This video script provides an in-depth discussion on aldehydes (alkanals), a class of organic compounds derived from alkanes. It covers the structural features, nomenclature, and differences between aldehydes and other alkane derivatives. The script explains the systematic IUPAC naming process, examples of aldehydes, and trivial names for common aldehydes. The video also delves into isomerism, including structural and functional isomers, and various reactions aldehydes undergo, such as oxidation and reduction. Lastly, the video highlights the synthesis of aldehydes from alcohols and alkenes, as well as their practical applications in daily life, such as in the production of formaldehyde and plastics.

Takeaways

• 😀 Aldehydes (alkanals) are derivatives of alkanes with the general formula CnH2nO, and their functional group is –CHO.
• 😀 The IUPAC naming of aldehydes involves selecting the longest carbon chain containing the –CHO group, naming it after the corresponding alkane, and replacing the suffix '-e' with '-al'.
• 😀 Aldehyde naming follows a systematic process that includes numbering the carbon chain from the functional group (which always gets the number 1), and naming any alkyl branches accordingly.
• 😀 Common examples of aldehydes include methanal, ethanol, and propanal. Their IUPAC names reflect their structure and carbon count.
• 😀 The trivial names of aldehydes are often used in everyday life, such as formaldehyde for methanal and acetaldehyde for ethanal.
• 😀 Aldehydes can have structural isomers (same molecular formula but different structures), such as butanal and 2-methylpropanal.
• 😀 Aldehydes can also have functional isomers, such as ketones, where the functional group differs (–CHO for aldehydes vs. –C=O for ketones).
• 😀 Aldehydes undergo oxidation reactions to form carboxylic acids, and they can be identified by reagents like Fehling’s and Tollens’ solutions.
• 😀 Aldehydes can be reduced to primary alcohols using reducing agents like hydrogen (H2). For example, acetaldehyde is reduced to ethanol.
• 😀 Aldehydes can be synthesized by oxidizing primary alcohols or through ozonization of alkenes, which breaks double bonds to form aldehydes.
• 😀 Aldehydes have practical applications, including in the production of formalin (a 40% solution of formaldehyde) and various types of thermosetting plastics.

Q & A

What is an aldehyde (alkanol), and how does it differ from other alkane derivatives?

An aldehyde (alkanol) is a derivative of an alkane with the general formula CnH2nO, and its structure features a carbonyl group (C=O) bonded to a hydrogen atom (C=O-H). This sets it apart from other alkane derivatives like alcohols and ethers, which have different functional groups.

What is the general naming process for aldehydes according to IUPAC?

To name aldehydes according to IUPAC, first identify the longest carbon chain containing the carbonyl group, then derive the name from the corresponding alkane by changing the suffix 'ane' to 'al'. The numbering starts from the carbonyl carbon, which is always assigned number 1.

Can you provide an example of IUPAC naming for aldehydes?

For example, if the longest chain contains four carbon atoms, the compound is named 'butanal.' If a methyl group is attached to the third carbon of the chain, the name becomes '3-methylbutanal.'

What are the common trivial names for aldehydes?

Trivial names for aldehydes include 'formaldehyde' for one-carbon aldehyde, 'acetaldehyde' for two-carbon, 'propionaldehyde' for three-carbon, and 'butyraldehyde' for four-carbon aldehydes.

What is the difference between structural isomers and functional isomers in aldehydes?

Structural isomers have the same molecular formula but different bonding arrangements. For example, butanal and 2-methylpropanal are structural isomers. Functional isomers, on the other hand, have the same molecular formula but differ in the type of functional group, such as aldehydes and ketones.

What reactions can aldehydes undergo?

Aldehydes can undergo oxidation reactions to form carboxylic acids, reduction reactions to form primary alcohols, and can be synthesized from the oxidation of primary alcohols or ozonization of alkenes.

What is the role of Fehling's reagent in identifying aldehydes?

Fehling's reagent is used to identify aldehydes by oxidizing them to carboxylic acids, resulting in the formation of a red precipitate of Cu2O, which confirms the presence of an aldehyde.

How does Tollens' reagent react with aldehydes?

Tollens' reagent contains silver ions (Ag+), which are reduced to metallic silver (Ag) when reacting with an aldehyde, forming a silver mirror on the container surface. This is another test for identifying aldehydes.

What is the reduction process for aldehydes, and what does it produce?

Aldehydes can be reduced to primary alcohols using a reducing agent such as hydrogen (H2). For instance, acetaldehyde (C2H4O) can be reduced to ethanol (C2H6O), where only the functional group changes, not the number of carbon atoms.

What are some applications of aldehydes in daily life?

Aldehydes are used in the production of formalin (a 40% solution of formaldehyde in water), which is used as a disinfectant and preservative, as well as in the production of certain plastics, including thermosetting plastics.