OCR A-Level Chemistry AS Breadth in chemistry (01), June 2019: Question 16
1 mark · Easy difficulty · Multiple Choice
Identify the correct statement about an electrophile from the given multiple-choice options.
Practise this questionQuestion
Question text
16 Which statement about an electrophile is correct?
A It is an electron pair acceptor.
B It is a proton donor.
C It is a negative ion.
D It is a species with an unpaired electron.
Your answer [1]
Mark scheme
Show the mark scheme
16 A 1 AO1.1
How to answer it
Question 16: Defining an Electrophile
What this question tests
This question assesses your recall and understanding of core definitions in organic reaction mechanisms (AO1.1). Specifically, it tests your ability to distinguish between key terminology such as electrophiles, nucleophiles, Brønsted-Lowry acids, and free radicals.
Core Definitions and Terminology
✅ Correct Answer: A
It is an electron pair acceptor.
An electrophile ("electron-lover") is attracted to regions of high electron density because it is deficient in electrons. It accepts a pair of electrons to form a new covalent bond.
💡 Key Knowledge
- Electrophile: Electron pair acceptor (e.g., NO₂⁺, Br⁺, H⁺).
- Nucleophile: Electron pair donor (e.g., NH₃, OH⁻, CN⁻).
- Proton donor: Definition of a Brønsted-Lowry acid (Statement B).
- Free radical: A species with an unpaired electron (Statement D).
🧠 Exam Technique
In multiple-choice questions involving definitions, read every option carefully before selecting. Watch out for distractors that describe related chemical species (like nucleophiles or radicals) to test if you confuse your terminology.
❌ Common Errors
- Confusing electrophiles with nucleophiles (electron pair donors).
- Assuming all electrophiles must be negative ions (many are positive ions like NO₂⁺ or polar molecules with a partial positive charge like HBr).
Topics
Module 4: Core organic chemistry · 4.1 Basic concepts and hydrocarbons
Question and mark scheme from the OCR A-Level Chemistry examination, AS Breadth in chemistry (01), June 2019. QuestionVault is an independent revision resource; questions remain the copyright of the awarding body.