Organic Chemistry Flashcards
What is an isomer?
Answer: Isomers are compounds that have the same molecular formula but different structural arrangements of atoms or functional groups.
What is the difference between a primary, secondary, and tertiary alcohol?
The difference between primary, secondary, and tertiary alcohols lies in the number of carbon atoms attached to the carbon atom that is bonded to the hydroxyl (-OH) group:
1. Primary Alcohol (1°): In a primary alcohol, the carbon attached to the -OH group is connected to only one other carbon atom. An example is ethanol (CH₃CH₂OH), where the -OH group is bonded to a carbon that is only attached to one other carbon.
2. Secondary Alcohol (2°): In a secondary alcohol, the carbon attached to the -OH group is connected to two other carbon atoms. An example is isopropanol (CH₃CHOHCH₃), where the -OH group is bonded to a carbon that is attached to two other carbons.
3. Tertiary Alcohol (3°): In a tertiary alcohol, the carbon attached to the -OH group is connected to three other carbon atoms. An example is tert-butanol (C(CH₃)₃OH), where the -OH group is bonded to a carbon attached to three other carbons.
What is an ether group?
Answer: An ether group (-O-) consists of an oxygen atom connected to two alkyl groups (R-O-R’).
What is a benzene ring?
Answer: A benzene ring is a six carbon ring with alternating double bonds (C₆H₆).
Functional groups like hydroxyl (-OH), methyl (-CH₃), and carboxyl (-COOH) can be attached to the benzene ring, forming compounds like phenols, toluene, and benzoic acid.
What are amides, and where are they found?
Answer: An amide group (-CONH₂) is formed when a carboxylic acid reacts with an amine or ammonia. Amides are found in proteins (as peptide bonds between amino acids) and many synthetic polymers like nylon.
What is the significance of the carbonyl group?
Answer: The carbonyl group (C=O) is polar, making molecules containing this group reactive. It is found in aldehydes, ketones, carboxylic acids, esters, and amides, and plays a major role in many organic reactions, including nucleophilic addition and substitution.
What is the role of an amino group in organic molecules?
Answer: The amino group (-NH₂) is characteristic of amines and amino acids. It is a basic functional group, capable of accepting a proton (H⁺), which makes it basic. In amino acids, the amino group is essential for forming peptide bonds.
What is an ester, and how is it formed?
Answer: An ester group (-COO-) is formed by the reaction of a carboxylic acid and an alcohol, in a reaction known as esterification. Esters are commonly found in fats, oils, and fragrances.
What is a carboxyl group?
Answer: A carboxyl group (-COOH) is a combination of a carbonyl group and a hydroxyl group. It is characteristic of carboxylic acids and gives the molecule acidic properties (ability to donate protons, H⁺).
What is the difference between an aldehyde and a ketone?
Answer: Both aldehydes and ketones contain a carbonyl group (C=O), but the key difference is the location of the group:
Aldehyde: The carbonyl group is attached to a hydrogen atom and a carbon chain (R-CHO).
Ketone: The carbonyl group is bonded to two carbon atoms (R-CO-R).
What is the significance of a hydroxyl group?
Answer: The hydroxyl group (-OH) is characteristic of alcohols. It is highly polar, making alcohols soluble in water and reactive in dehydration and oxidation reactions.
What is a functional group?
Answer: A functional group is a specific group of atoms within a molecule that is responsible for the characteristic reactions of that molecule. Functional groups largely determine the chemical behavior of the molecules they are part of.
What are the two main types of isomers?
Answer: The two main types of isomers are:
Structural (or Constitutional) Isomers: Isomers that differ in the connectivity of atoms (i.e., the way atoms are bonded together).
Stereoisomers: Isomers that have the same connectivity but differ in the spatial arrangement of atoms or groups.
What are stereoisomers?
Answer: Stereoisomers have the same molecular formula and the same connectivity of atoms, but differ in the three-dimensional arrangement of atoms or groups in space.
What is a chiral center (stereocenter)?
Answer: A chiral center is a carbon atom that is attached to four different groups, making it asymmetric. Molecules with one or more chiral centers can exist as enantiomers, which are mirror-image isomers that are not superimposable.
What are enantiomers?
Answer: Enantiomers are a type of stereoisomer. They are mirror-image molecules that cannot be superimposed on one another, similar to how your left and right hands are mirror images but not identical.
What are cis-trans isomers?
Answer: Cis-trans isomerism occurs due to restricted rotation around a double bond or ring. In cis isomers, similar groups are on the same side of the double bond or ring, while in trans isomers, the similar groups are on opposite sides.
What’s a primary alcohol?
A primary alcohol is an alcohol in which the carbon atom bonded to the hydroxyl group (–OH) is also bonded to only one other carbon atom (or none if it’s methanol).
What’s a secondary alcohol?
A secondary alcohol is an alcohol where the hydroxyl group (–OH) is attached to a secondary carbon atom—a carbon that is bonded to two other carbon atoms.
What is a tertiary alcohol?
A tertiary alcohol is an alcohol where the hydroxyl group (–OH) is attached to a tertiary carbon atom—a carbon that is bonded to three other carbon atoms.
