Organic Chemistry Flashcards
7 cards from real OAT practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Organic Chemistry flashcards as text
Which reagent converts a primary alcohol to an aldehyde without over-oxidizing to a carboxylic acid?
Answer: PCC (pyridinium chlorochromate)
PCC oxidizes primary alcohols to aldehydes and stops there because it is used in anhydrous conditions.
In an E2 elimination reaction, the leaving group and the β-hydrogen must be in what geometric relationship?
Answer: Anti-periplanar (180°)
E2 requires a concerted anti-periplanar arrangement so the base, β-H, Cα, and leaving group are all coplanar.
What is the product when benzene reacts with Cl2 in the presence of FeCl3?
Answer: Chlorobenzene
FeCl3 activates Cl2 as an electrophile, enabling electrophilic aromatic substitution to give chlorobenzene.
Which of the following molecules exhibits optical activity?
Answer: 2-butanol
2-Butanol has a chiral center (C2 bonded to OH, H, CH3, and C2H5), making it optically active.
Which functional group is introduced when a terminal alkyne reacts with water in the presence of H2SO4 and HgSO4?
Answer: Ketone
Markovnikov addition of water to an internal position of a terminal alkyne forms a methyl ketone via an enol intermediate.
The reaction of an ester with excess Grignard reagent yields which product?
Answer: A tertiary alcohol
Two equivalents of Grignard reagent add to an ester—the first forms a ketone intermediate that reacts with the second—yielding a tertiary alcohol.
Which of the following is the strongest acid?
Answer: Acetic acid (pKa ≈ 4.75)
Acetic acid has the lowest pKa (~4.75), meaning it donates a proton most readily due to resonance stabilization of the acetate anion.