SCH4U /GRADE 12 CHEM: STRUCTURE &
PROPERTIES OF MATTER EXAM QUESTIONS AND
CORRECT ANSWERS (VERIFIED ANSWERS) Q&A
2027 INSTANT DOWNLOAD PDF
1. Which quantum number describes the main energy level of
an electron?
A. Azimuthal quantum number (ℓ)
B. Magnetic quantum number (mℓ)
C. Principal quantum number (n)
D. Spin quantum number (ms)
Correct Answer: C. Principal quantum number (n)
Rationale: The principal quantum number indicates the
electron's primary energy level and relative distance from the
nucleus.
2. Which orbital can hold a maximum of two electrons?
A. s orbital
B. p subshell
C. d subshell
D. f subshell
Correct Answer: A. s orbital
,Rationale: Every orbital can hold a maximum of two electrons
with opposite spins. An s subshell contains only one orbital.
3. How many electrons can occupy the p subshell?
A. 2
B. 4
C. 6
D. 10
Correct Answer: C. 6
Rationale: A p subshell contains three orbitals, each holding
two electrons (3 × 2 = 6).
4. Which principle states that electrons occupy the lowest
available energy orbitals first?
A. Hund's Rule
B. Pauli Exclusion Principle
C. Aufbau Principle
D. Heisenberg Principle
Correct Answer: C. Aufbau Principle
Rationale: The Aufbau Principle describes the order in which
electrons fill orbitals.
,5. According to Hund's Rule, electrons in equal-energy orbitals
will first:
A. Pair immediately
B. Occupy separate orbitals with parallel spins
C. Fill highest energy orbitals first
D. Have opposite spins
Correct Answer: B. Occupy separate orbitals with parallel spins
Rationale: This minimizes electron-electron repulsion.
6. Which element has the electron configuration 1s²2s²2p⁶3s¹?
A. Sodium
B. Magnesium
C. Neon
D. Aluminum
Correct Answer: A. Sodium
Rationale: Sodium has 11 electrons.
7. Which quantum number identifies the shape of an orbital?
A. n
B. ℓ
C. mℓ
D. ms
Correct Answer: B. ℓ
, Rationale: The azimuthal quantum number determines orbital
shape.
8. Which orbital has a dumbbell shape?
A. s
B. p
C. d
D. f
Correct Answer: B. p
Rationale: p orbitals have two lobes resembling a dumbbell.
9. What is the maximum number of electrons in the n = 3
energy level?
A. 8
B. 10
C. 18
D. 32
Correct Answer: C. 18
Rationale: Maximum electrons = 2n² = 2(3²) = 18.
10. Which particle determines the identity of an element?
A. Electron
B. Neutron
PROPERTIES OF MATTER EXAM QUESTIONS AND
CORRECT ANSWERS (VERIFIED ANSWERS) Q&A
2027 INSTANT DOWNLOAD PDF
1. Which quantum number describes the main energy level of
an electron?
A. Azimuthal quantum number (ℓ)
B. Magnetic quantum number (mℓ)
C. Principal quantum number (n)
D. Spin quantum number (ms)
Correct Answer: C. Principal quantum number (n)
Rationale: The principal quantum number indicates the
electron's primary energy level and relative distance from the
nucleus.
2. Which orbital can hold a maximum of two electrons?
A. s orbital
B. p subshell
C. d subshell
D. f subshell
Correct Answer: A. s orbital
,Rationale: Every orbital can hold a maximum of two electrons
with opposite spins. An s subshell contains only one orbital.
3. How many electrons can occupy the p subshell?
A. 2
B. 4
C. 6
D. 10
Correct Answer: C. 6
Rationale: A p subshell contains three orbitals, each holding
two electrons (3 × 2 = 6).
4. Which principle states that electrons occupy the lowest
available energy orbitals first?
A. Hund's Rule
B. Pauli Exclusion Principle
C. Aufbau Principle
D. Heisenberg Principle
Correct Answer: C. Aufbau Principle
Rationale: The Aufbau Principle describes the order in which
electrons fill orbitals.
,5. According to Hund's Rule, electrons in equal-energy orbitals
will first:
A. Pair immediately
B. Occupy separate orbitals with parallel spins
C. Fill highest energy orbitals first
D. Have opposite spins
Correct Answer: B. Occupy separate orbitals with parallel spins
Rationale: This minimizes electron-electron repulsion.
6. Which element has the electron configuration 1s²2s²2p⁶3s¹?
A. Sodium
B. Magnesium
C. Neon
D. Aluminum
Correct Answer: A. Sodium
Rationale: Sodium has 11 electrons.
7. Which quantum number identifies the shape of an orbital?
A. n
B. ℓ
C. mℓ
D. ms
Correct Answer: B. ℓ
, Rationale: The azimuthal quantum number determines orbital
shape.
8. Which orbital has a dumbbell shape?
A. s
B. p
C. d
D. f
Correct Answer: B. p
Rationale: p orbitals have two lobes resembling a dumbbell.
9. What is the maximum number of electrons in the n = 3
energy level?
A. 8
B. 10
C. 18
D. 32
Correct Answer: C. 18
Rationale: Maximum electrons = 2n² = 2(3²) = 18.
10. Which particle determines the identity of an element?
A. Electron
B. Neutron
