ConceptConceptDocsDocuments

CAIE A-Level Chemistry 1.3.7 Electrons-in-Boxes Notation

Practise drawing orbital boxes and using arrows to identify paired and unpaired electrons in atoms or ions.

Syllabus
2028–2030
Course
Chemistry 9701
Level
AS

Exam points

  • draw one box per orbital and no more than two opposite-spin electrons in each box
  • fill degenerate orbitals singly with parallel spins before pairing electrons
  • use the completed diagram to count electron pairs or unpaired electrons in atoms and ions

1.3.7—The electrons in boxes notation question 1

[Maximum number: 1]

Complete the diagram to show the arrangement of electrons within the third shell of a phosphorus atom.

3s

3s

Figure for Question 1.3.7—The electrons in boxes notation question 1 — CAIE A-Level Chemistry AS
3p

3p

Figure for Question 1.3.7—The electrons in boxes notation question 1 — CAIE A-Level Chemistry AS
All question bank results loaded